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                                   UNIVISION CENTER

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                                OFFICE LEASE AGREEMENT

                                       Between

                              BEVERLY HILLS CENTER LLC
                                    as Landlord

                                         and

                      COMMUNICATION TELESYSTEMS INTERNATIONAL
                          DBA WORLDXCHANGE COMMUNICATIONS
                                     as Tenant




                                        Dated

                                     May 30, 1998






                                  TABLE OF CONTENTS



                                                                                 Page
                                                                           
Paragraph 1.  DEFINITIONS AND BASIC PROVISION    . . . . . . . . . . . . . . . . . .1

Paragraph 2.  GRANTING CLAUSE  . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Paragraph 3.  EARLY OCCUPANCY  . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Paragraph 4.  RENTAL . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2

Paragraph 5.  USE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Paragraph 6.  SERVICES TO BE PROVIDED BY LANDLORD  . . . . . . . . . . . . . . . . .3

Paragraph 7.  REPAIR AND MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . .5

Paragraph 8.  FIRE OR OTHER CASUALTY . . . . . . . . . . . . . . . . . . . . . . . .5

Paragraph 9.  COMPLIANCE WITH LAWS AND USAGE . . . . . . . . . . . . . . . . . . . .6

Paragraph 10. LIABILITY AND INDEMNITY  . . . . . . . . . . . . . . . . . . . . . . .6

Paragraph 11. ADDITIONS AND FIXTURES . . . . . . . . . . . . . . . . . . . . . . . .7

Paragraph 12. ASSIGNMENT AND SUBLETTING  . . . . . . . . . . . . . . . . . . . . . .7

Paragraph 13. SUBORDINATION  . . . . . . . . . . . . . . . . . . . . . . . . . . . .9

Paragraph 14. OPERATING EXPENSES . . . . . . . . . . . . . . . . . . . . . . . . . 10

Paragraph 15. EMINENT DOMAIN . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Paragraph 16. ACCESS BY LANDLORD . . . . . . . . . . . . . . . . . . . . . . . . . 12

Paragraph 17. LANDLORD'S LIEN  . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Paragraph 18. DEFAULTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13

Paragraph 19. NONWAIVER  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Paragraph 20. HOLDING OVER . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14

Paragraph 21. COMMON AREA. . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Paragraph 22. RULES AND REGULATIONS  . . . . . . . . . . . . . . . . . . . . . . . 15

Paragraph 23. TAXES  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Paragraph 24. INSURANCE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Paragraph 25. PARKING  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15

Paragraph 26. PERSONAL LIABILITY . . . . . . . . . . . . . . . . . . . . . . . . . 16

Paragraph 27. NOTICE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Paragraph 28. LANDLORD'S MORTGAGE  . . . . . . . . . . . . . . . . . . . . . . . . 16

Paragraph 29. BROKERAGE  . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Paragraph 30. PREPAID RENTAL AND SECURITY DEPOSIT  . . . . . . . . . . . . . . . . 16

Paragraph 31. SPRINKLERS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 16

Paragraph 32. INTERCONNECTION RIGHTS . . . . . . . . . . . . . . . . . . . . . . . 17

Paragraph 33. EMERGENCY GENERATOR  . . . . . . . . . . . . . . . . . . . . . . . . 18


                                      i




Paragraph 34. SUPPLEMENTAL HVAC  . . . . . . . . . . . . . . . . . . . . . . . . . 18

Paragraph 35. DELIVERY OF PREMISES . . . . . . . . . . . . . . . . . . . . . . . . 19

Paragraph 36. REMOVAL OF ABOVE-CEILING ALTERATIONS . . . . . . . . . . . . . . . . 19

Paragraph 37. RENEWAL OPTIONS  . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Paragraph 38. ROOFTOP RIGHTS . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Paragraph 39. MISCELLANEOUS  . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Paragraph 40. ENTIRE AGREEMENT AND BINDING EFFECT  . . . . . . . . . . . . . . . . 23

EXHIBIT A     LEASED PREMISES

EXHIBIT B     LAND

EXHIBIT C     RULES AND REGULATIONS












                                     ii




                            OFFICE LEASE AGREEMENT

1. DEFINITIONS AND BASIC PROVISIONS.

     A. Date of Lease: MAY 26, 1998.      1.E (1) Foothill Capital  Corporation
                                                 11111 Santa Monica Boulevard
     B. "Landlord": Beverly Hills Center LLC     Suite 1500
                                                 Los Angeles, CA 90025
     C. Address of Landlord:                     Attn: Documentation Department
                       2323 Bryan Street, Suite 2020
                       Lock Box 120
                       Dallas, Texas 75201

     D. "Tenant":      Communication Telesystems International
                       dba WorldxChange Communications

     E. Address of Tenant:
                       9999 WILLOW CREEK ROAD
                       ----------------------
                       SAN DIEGO, CA 92131
                       ----------------------

          F.   "Building": The structure commonly known as the Univision Center
and which is located on the 0.8437 acre tract of land (the "Land") described by
metes and bounds on EXHIBIT B attached hereto and made a part hereof for all
purposes and whose address is 2323 Bryan Street, Dallas, Texas 75201.

          G.   "Leased Premises": Approximately 6,598 square feet of rentable
area on the fifteenth (15th) floor of the Building, as outlined and hatched on
the floor plan attached hereto as EXHIBIT A and made a part hereof for all
purposes. Tenant acknowledges that Tenant has had the opportunity to measure the
Leased Premises and that there has been applied to the usable square footage of
the Leased Premises a common area factor to arrive at the rentable square
footage of the Leased Premises. Therefore, Landlord and Tenant hereby stipulate
that notwithstanding anything herein to the contrary, the Leased Premises shall
be deemed to consist of 6,598 rentable square feet, and that no shortage or
overage in the rentable square feet of the Leased Premises purported by either
party shall be the basis for changing the number of rentable square feet herein
stipulated.

          H.   "Project": The Building, the parking facilities, parking garage,
the Skybridge and other structures, improvements, landscaping, fixtures,
appurtenances and other common areas now or hereafter, constructed or erected on
the Land.

          I.   "Rentable area in the Building" shall be 464,542 square feet of
rentable area, unless modified as provided herein.

          J.   "Commencement Date": February 15, 1998, or the date upon which
Tenant occupies the Leased Premises with the prior written consent of Landlord,
whichever shall first occur. Upon request of either party hereto, Landlord and
Tenant agree to execute and deliver a written declaration in recordable form
expressing the Commencement Date hereof.

          K.   "Term": Commencing on the Commencement Date and ending five (5)
years after the Commencement Date, plus any partial calendar month following the
Commencement Date, unless sooner terminated as provided herein.

          L.   "Base Rental" $164,950.00 per year for the first five (5) years
of the Term of this Lease, representing rental of $164,950.00 per year with
respect to the Leased Premises and a riser fee (the "Riser Fee") of $- 0 - per
year based upon Tenant's installation of nine (9) diameter inches of conduits or
equivalent cable runs (the "Initial Conduits") in the riser facilities of the
Building, payable in equal monthly installments of $13,745.83 each; each such
monthly installment shall be due and payable on the first day of each calendar
month, monthly in advance without demand and without setoff or deduction
whatsoever, except as otherwise specifically stated in this Lease. In the event
at Tenant's request Landlord permits Tenant to install additional conduits or
equivalent cable runs, Tenant shall pay an additional riser fee with respect to
such additional installations in an amount equal to the then prevailing market
riser fee rate; provided, however, that during the first five (5) years of the
Term, such additional riser fee shall be $250.00 per month per diameter inch of
additional conduit or equivalent cable run. The foregoing shall apply to all
conduits and equivalent cable runs used by Tenant, including, without
limitation, conduits and equivalent cable runs related to Tenant's
interconnection rights set forth in Paragraph 32, the Generator Installation and
the HVAC Installation (as defined in Paragraphs 33 and 34, respectively) which
exceed the Initial Conduits.

          M.   "Prepaid Rental": $13,745.83, to be applied to the first accruing
monthly installments of rental.


                                  -1-




          N.   "Security Deposit": $13,745.83.

          0.   "Permitted Use": The Leased Premises shall be used only for
office purposes and/or for the installation, maintenance, and operation of a
telecommunications facility, switching, operations and terminal service and
repair of Tenant's equipment and storage.

          P.   "Common Area": That part of the Project designated by Landlord
from time to time for the common use of all tenants, including among other
facilities, the Skybridge, sidewalks, service corridors, curbs, truckways,
loading areas, private streets and alleys, lighting facilities, mechanical and
electrical rooms, janitors' closets, halls, lobbies, delivery passages,
elevators, drinking fountains, meeting rooms, public toilets, parking areas and
garages, decks and other parking facilities, landscaping and other common rooms
and common facilities.

          Q.   "Prime Rate": The rate announced as such from time to time by
Chase Manhattan Bank, N.A., or its successors, at its principal office.

          R.   "Broker": The MTA Company

          S.   "Parking": Three (3) parking spaces, subject, however, to the
payment of prevailing market rental established from time to time for similar
parking spaces and further subject to the other terms, covenants and conditions
specified in Paragraph 25 hereof. Notwithstanding the foregoing or anything in
Paragraph 25 to the contrary, during the first five (5) years of the Term,
Tenant's rental obligations with respect to such three (3) parking spaces shall
be $120.00 (plus applicable taxes) per month per parking space utilized for a
vehicle and $250.00 (plus applicable taxes) per month per parking space utilized
for equipment.

          T.   "Base Operating Expenses Rate": The Actual Operating Expenses
Rate for the 1998 calendar year.

          U.   "Skybridge": The aerial walkway connecting the Building with the
Plaza of the Americas, together with any alterations, improvements and/or
replacements thereof.

          Each of the foregoing definitions and basic provisions shall be
construed in conjunction with the references thereto contained in the other
provisions of this Lease and shall be limited by such other provisions. Each
reference in this Lease to any of the foregoing definitions and basic provisions
shall be construed to incorporate each term set forth above under such
definition or provision.

     2.   GRANTING CLAUSE. Landlord, in consideration of the covenants and
agreements to be performed by Tenant and upon the terms and conditions
hereinafter stated, does hereby lease, demise and let unto Tenant, and Tenant
does hereby lease from Landlord, the Leased Premises specified in Paragraph 1.G.
hereof to have and to hold for the Term of this Lease, as specified in Paragraph
1.K. hereof.

     3.   EARLY OCCUPANCY. Landlord shall permit Tenant and Tenant's agents
to enter the Leased Premises prior to the Commencement Date in order that
Tenant may perform the Tenant Finish Work (as defined in Paragraph 35 hereof)
through Tenant's own contractors. The foregoing license to enter prior to the
Commencement Date is conditioned upon Tenant's workmen and mechanics working
in harmony and not materially interfering with the labor employed by
Landlord, Landlord's mechanics or contractors or with any other tenant or
their contractors. Such license is further conditioned upon workers'
compensation and public liability insurance and property damage insurance,
all in amounts and with companies and on forms reasonably satisfactory to
Landlord, being provided and at all times maintained by Tenant's contractors
engaged in the performance of the Tenant Finish Work, and certificates of
such insurance being furnished to Landlord prior to proceeding with the work.
If at any time such entry shall cause material disharmony or interference to
other tenants, contractors or labor for any reason whatsoever including,
without limitation, strikes or other work stoppages and if Tenant has not
caused such disharmony or interference to cease promptly following notice
thereof to Tenant, then this license may be revoked by Landlord until such
disharmony or interference ceases. Any occupancy of the Leased Premises by
Tenant prior to the Commencement Date shall be subject to all of the terms
and provisions of this Lease excepting only those requiring the payment of
rental and other charges.

     4.   RENTAL. As rental for the lease and use of the Leased Premises,
Tenant will pay Landlord or Landlord's assigns, at the address of Landlord
specified in Paragraph 1.C. hereof, without demand and without deduction,
abatement or setoff (except as otherwise expressly provided for herein in
Paragraph 6 hereof, Paragraph 8 hereof and Paragraph 15 hereof), the Base
Rental in the manner specified in Paragraph 1.L. hereof, in lawful money of
the United States. If the Term of this Lease does not commence on the first
day of a calendar month, tenant shall pay to landlord in advance a pro rata
part of such sum as rental for such first partial month. Tenant shall not pay
any installment of rental more than one (1) month in advance. All past due
installments of rental or other payment specified herein after applicable
notice and cure period shall bear interest at the highest lawful rate per
annum from the date due until paid.

     If Tenant fails to timely pay two (2) consecutive installments of Base
Rental, or other payment specified herein, or any combination thereof, after
any applicable notice and cure period, Landlord may require Tenant to


                                    -2-




pay (in addition to any interest) Base Rental and other payments specified
herein (as reasonably estimated by Landlord, if necessary) quarterly in
advance, and, in such event, all future payments shall be made on or before
the due date in cash or by cashier's check or money order, and the delivery
of Tenant's personal or corporate check shall no longer constitute payment
thereof. Any acceptance of Tenant's personal or corporate check thereafter by
Landlord shall not be construed as a waiver of the requirement that such
payments be made in cash or by cashier's check or money order. Any amount so
estimated by Landlord and paid by Tenant shall be adjusted promptly after
actual figures become available and paid or credited to Landlord or Tenant,
as the case may be.

     5.   USE. Tenant shall use the Leased Premises solely for the Permitted Use
specified in Paragraph 1.O hereof and for no other business or purpose without
the prior written consent of Landlord.

     6.   SERVICES TO BE PROVIDED BY LANDLORD.

          A.   Subject to the rules and regulations hereinafter referred to,
Landlord shall furnish Tenant, at Landlord's expense, the following services
during the Term of this Lease:

          (1)  Air conditioning and heating in season, at such times as Landlord
     normally furnishes such services to other tenants in the Building, and at
     such temperatures and in such amounts as are reasonably considered by
     Landlord to be standard, but such service on Saturday afternoons, Sundays
     and holidays to be furnished only upon the request of Tenant, who shall
     bear the actual cost thereof. Tenant acknowledges that such service and
     temperature may be subject to change by local, county, state or federal
     regulation. Whenever machines or equipment that generate abnormal heat are
     used in the Leased Premises which affect the temperature otherwise
     maintained by the air conditioning system, Landlord shall have the right to
     install supplemental air conditioning in the Leased Premises, and the
     reasonable cost thereof, including the cost of installation, operation, use
     and maintenance, shall be paid by Tenant to Landlord as additional rental
     upon demand.

          (2)  Hot and cold water at those points of supply provided for general
     use.

          (3)  Janitor service in and about the Building, and the Leased
     Premises, as may be reasonably required; however, Tenant shall pay the
     additional costs attributable to the cleaning of improvements within the
     Leased Premises other than building standard improvements.

          (4)  Elevators for ingress to and egress from the Building as may be
     reasonably required. Landlord may reasonably limit the number of elevators
     in operation after usual and customary business hours and on Saturday
     afternoons, Sundays and legal holidays, but, in all events except in cases
     of emergency, at least one elevator shall be available.

          (5)  Replacement of fluorescent lamps in the building standard ceiling
     mounted fixtures installed by Landlord and incandescent bulb replacement in
     all public areas.

          (6)  24 hours access to the Leased Premises, subject to Landlord's
     reasonable security measures.

          B.   Landlord shall provide or cause to be provided to the Leased
Premises electrical current equal to the capacity of 200 amps, 480 volts
which shall originate from the Building's provided busway. Tenant shall be
responsible, at Tenant's sole cost, for the installation and disconnection of
Tenant's equipment and all costs to transform such electrical service to meet
Tenant's electrical needs, including, without limitation, the purchase and
installation of any transformers. Provided Tenant makes such election and
performs such work during the construction of the Tenant Finish Work,
Landlord shall increase Tenant's electrical capacity, provided Tenant pays to
Landlord an amount equal to $7,500.00 for each increase of 200 amps, 480
volts and that Tenant pay all costs related to the installation and
disconnection of Tenant's equipment and all costs to transform such
additional electrical service to meet Tenant's electrical needs. Without
Landlord's prior written consent, which consent shall not be unreasonably
withheld, Tenant shall not install any equipment which would result in
Tenant's connected load exceeding 3.0 watts per square foot of rentable area
within the Leased Premises or which would generate sufficient heat to affect
the temperature otherwise maintained in the Leased Premises by the normal
operation of the Building air conditioning equipment serving the Leased
Premises. The obligation of Landlord to provide or cause to be provided
electrical service shall be subject to the rules and regulations of the
supplier of such electricity and of any municipal or other governmental
authority regulating the business of providing electrical utility service.
Landlord shall not be liable or responsible to Tenant for any loss, damage or
expense which Tenant may sustain or incur if either the quantity or character
of the electric service is changed or is no longer available or no longer
suitable for Tenant's requirements. At any time when Landlord is furnishing
electric current to the Leased Premises pursuant to this Paragraph 6.B.,
Landlord may, at its option, upon not less than thirty (30) days prior
written notice to Tenant, discontinue the furnishing of such electric
current. If Landlord gives such notice of discontinuance, Landlord shall make
all reasonably necessary arrangements with the public utilities supplying the
electric current to the Project (as defined in Paragraph 14) with respect to
connecting electric current to the Leased Premises, but Tenant shall contract
directly with such public utility with respect to supplying such service.
Electrical usage in the Leased Premises shall be measured by installing a
submeter. The cost of purchase and installation of a submeter in the Leased
Premises shall be borne by Tenant.


                                      -3-



          C.   Tenant shall be obligated to pay to Landlord, as additional
rental, (1) Tenant's proportionate share of all electrical service to the Common
Area (collectively, "Common Area Electrical Service") and (2) the cost of
electrical service to the Leased Premises. Tenant's proportionate share of the
cost of Common Area Electrical Service shall be equal to the actual cost of such
service times a fraction in which the numerator is the rentable area of the
Leased Premises and the denominator is the rentable area of the Building. The
electrical service to the Leased Premises shall be submetered at Tenant's
expense. The cost of electrical service shall include without limitation all
fuel adjustment charges, demand charges and taxes. If, during any period of
time, the Building is 95% or less leased, then, for purposes of this Paragraph
6.C., the area of the Building shall be deemed to mean and include that portion
of the Building which is occupied (calculated on the basis of rentable area).


          D.   Prior to the Commencement Date, Landlord shall deliver to Tenant
a statement which sets forth the Estimated Monthly Charge (as hereinafter
defined) due and payable by Tenant under the terms of Paragraph 6.C. hereof for
electrical service each month during the Term. Tenant shall pay to Landlord on
the first day of each calendar month during the Term, commencing with the
Commencement Date, as additional rental, the Estimated Monthly Charge. In the
event the Commencement Date occurs on a day other than the first day of a
calendar month, the Estimated Monthly Charge payable in respect of the month in
which the Commencement Date falls shall be prorated and the Estimated Monthly
Charge, as so prorated, shall be due and payable on or before the Commencement
Date. Thereafter, as the actual amounts owed by Tenant for Tenant's
proportionate share of Common Area Electrical Service and electrical service to
the Leased Premises are determined, Landlord shall deliver to Tenant a statement
setting forth the electrical service utilized during the period in question and
the actual amount owed by Tenant under the terms of Paragraph 6.C. hereof in
respect of such electrical service. If the Estimated Monthly Charge previously
paid by Tenant is less than the amount owed by Tenant based upon Landlord's
actual utility bills (for the period covered in such bills), Tenant shall pay to
Landlord the amount of the deficiency for such period within ten (10) days after
receipt of Landlord's statement. In the event the Estimated Monthly Charge
exceeds Tenant's proportionate share of such costs, the excess payment shall be
credited against subsequent amounts due from Tenant for electrical service or
paid promptly to Tenant if the Term of this Lease has expired. From time to time
Landlord shall review the Estimated Monthly Charge and make such adjustments as
may appear to be appropriate in the reasonable discretion of Landlord. Landlord
shall have the right to revise the Estimated Monthly Charge at any time and from
time to time in the exercise of Landlord's reasonable judgment upon at least ten
(10) days prior written notice to Tenant. All payments due under this paragraph
6.D. after the expiration of such ten (10) day period shall be increased or
decreased as may be required to make such payments consistent with such revised
Estimated Monthly Charge. As used in this Paragraph 6.D., the term "Estimated
Monthly Charge" shall mean Landlord's reasonable estimate of the amount due and
payable by Tenant each month during the Term with respect to Tenant's
proportionate share of Common Area Electrical Service and electrical service to
be provided to the Leased Premises.

          E.   If Tenant's connected load for electrical design exceeds 3.0
watts per square foot and Tenant's usage is not being measured per subparagraph
B. above, Tenant shall pay as a surcharge a proportionate part of all electrical
service costs which are attributable to the aggregate over-standard electrical
consumption by all tenants in the Building. Such proportion shall be equal to
the product of the aggregate cost of all over-standard electrical consumption in
the Building (as reasonably determined by Landlord) times a fraction in which
the numerator is Tenant's electrical design load in excess of 3.0 watts per
square foot and the denominator is the aggregate of the total electrical design
load of all tenants in the Building in excess of 3.0 watts per square foot.
Tenant's proportionate share of such sums shall be due within ten (10) days
after the date of receipt of a statement therefor from Landlord setting forth
the amount of the charges involved and calculating Tenant's proportionate share
thereof.

          F.   No interruption or malfunction of any of such services shall
constitute an eviction or disturbance of Tenant's use and possession of the
Leased Premises or the Building or a breach by Landlord of any of Landlord's
obligations hereunder or render Landlord liable for damages or entitle Tenant to
be relieved from any of Tenant's obligations hereunder (including the obligation
to pay rental) or grant Tenant any right of setoff or recoupment. In the event
of any such interruption, however, Landlord shall use reasonable diligence to
restore such service or cause same to be restored in any circumstances in which
such restoration is within the reasonable control of Landlord. Notwithstanding
the foregoing, in the event that an interruption of any of those services to be
provided by Landlord under this Paragraph 6 shall render the Leased Premises
untenantable, such interruption was not caused by any act or omission of Tenant
or Tenant's employees, agents or contractors and such interruption shall
continue for a period in excess of five (5) consecutive business days, then
Tenant's Base Rental obligations under the Lease shall abate for such period
which exceeds five (5) consecutive business days; provided, however, that such
rental abatement shall be on a pro rata basis to reflect only that portion of
the Leased Premises affected by the interruption of services. The abatement of
rent provided for in this paragraph shall not be applicable in the case of any
interruption or malfunction resulting from a reduction or elimination of
electrical service to the Building from the electrical utility company or
governmental agency providing such electrical service or change in quality of
such service, nor shall such abatement be applicable in the event of any
interruption or malfunction of services due to regulations of any government or
governmental authority or any utility company providing electrical service
provided such interruption or malfunction is not due to the failure of Landlord
to make payment for such service or the failure to comply or perform its
contractual obligations or Landlord's failure to comply with existing applicable
rules or regulations. In the event (i) such interruption of services (A) was not
the result of a casualty described in


                                   -4-



Paragraph 8 of this Lease, (B) was not caused in whole or in part by Tenant or
Tenant's agents, employees or contractors, and (C) renders the Leased Premises
untenantable, (ii) the curing of such interruption of services is within the
reasonable control of Landlord, and (iii) such interruption of services shall
not be cured within sixty (60) days following the occurrence of such
interruption, Tenant shall have the right to terminate this Lease by delivering
to Landlord sixty (60) days notice of such termination.

          G.   Should Tenant desire any additional services beyond those
described in this Paragraph 6 hereof or rendition of any of such services
outside the normal times of Landlord for providing such service, Landlord may
(at Landlord's option), upon reasonable advance notice from Tenant to Landlord,
furnish such services, and Tenant agrees to pay Landlord such charges as may be
agreed on between Landlord and Tenant, but in no event at a charge less than
Landlord's actual cost plus overhead for the additional services provided.

     7.   REPAIR AND MAINTENANCE.

          A.   Landlord shall, at Landlord's own cost and expense, except as may
be provided elsewhere herein, make necessary repairs of damage to the Building
corridors, lobby, structural members of the Building and equipment used to
provide the services referred to in Paragraph 6 hereof, except to the extent any
such damage is caused by acts or omission of Tenant, or Tenant's agents,
employees or invitees, in which event, Tenant shall bear the cost of such
repairs to the extent so caused by Tenant, or Tenant's agents, employees or
invitees. Tenant shall promptly give Landlord notice of any damage in the Leased
Premises requiring repair by Landlord, as aforesaid.

          B.   Tenant shall not in any manner deface or injure the Leased
Premises or the Building but shall maintain the Leased Premises, including,
without limitation, all fixtures installed by Tenant and all plate glass, walls,
carpeting and other floor covering placed or found therein, in a clean,
attractive, first-class condition and in good repair, except as to damage
required to be repaired by Landlord, as provided in Paragraph 7.A. hereof. Upon
the expiration of the Term of this Lease, Tenant shall surrender and deliver up
the Leased Premises with all improvements located thereon (except as provided in
Paragraph 11.B. hereof) to Landlord broom-clean and in the same condition in
which they existed at the commencement of the Lease, excepting only ordinary
wear and tear and damage arising from any cause not required to be repaired by
Tenant, failing which Landlord may restore the Leased Premises to such
condition, and Tenant shall pay the cost thereof.

     8.   FIRE AND OTHER CASUALTY.

          A.   Notwithstanding anything in the Lease to the contrary, if the
Leased Premises or any portion of the Building shall be damaged or destroyed by
fire or other casualty, then Landlord shall have the right, at its sole
election, to terminate the Lease with written notice thereof to Tenant, but only
in the event that any one of the following conditions is met or circumstances
apply:

               (i)     such event of casualty shall occur in the last twelve
          (12) months of the Term of the Lease;

               (ii)    such event of casualty is not covered by the property
          insurance policy or policies procured and maintained by Landlord with
          respect to the Building and the Leased Premises, and the necessary
          repair and restoration of the Leased Premises and/or the Building
          would cost in excess of $500,000.00;

               (iii)   the mortgagee under any mortgage or deed of trust
          covering the Building shall require that any insurance proceeds
          payable as a result of such event of casualty be withheld and applied
          against the mortgage debt, and the necessary repair and restoration of
          the Leased Premises and/or the Building would cost in excess of
          $500,000.00; or

               (iv)    all other leases in the Building are terminated as a
          result of such event of casualty.

          B.   In the event that Landlord shall not elect (or should not have
the right to elect) to terminate the Lease in the event of casualty as provided
above, and subject to Tenant's not exercising its right to terminate the Lease
in the event of casualty as hereinafter provided, Landlord, using all due
diligence, shall repair and restore the Building and the Leased Premises to
substantially the same condition in which they existed prior to such damage or
destruction, except that Landlord shall in no event be required to rebuild,
repair or replace any part of the partitions, fixtures and other improvements
installed by Tenant or other tenants within the Building.

          C.   In the event that the Leased Premises are damaged or destroyed by
fire or other casualty, or a portion of the Building is damaged or destroyed by
fire or other casualty so as to materially impair the use and occupancy by
Tenant of the Leased Premises, then Landlord shall be obligated to provide
written notice (the "Restoration Notice") to Tenant within sixty (60) days of
such event of casualty stating a good faith estimate, certified by an
independent architect, of the period of time (the "Stated Restoration Period")
which shall be required for the repair and restoration of the Leased Premises
and/or the Building. Tenant shall have the right, at its election, to terminate
the Lease if (i) such event of casualty shall occur in the last twelve (12)
months of the Term of the Lease, or (ii) either (A) the Stated Restoration
Period shall be in excess of one hundred eighty (180) days following the event
of casualty and Tenant terminates the Lease with written notice thereof to
Landlord within thirty (30) days following delivery of the Restoration Notice,
or (B) Landlord shall fail to substantially


                                       -5-



complete the repair and restoration of the Leased Premises or the Building
within the Stated Restoration Period (subject to extension as provided in
Paragraph 32.T. of the Lease) and Tenant delivers written notice of such
termination to Landlord within ten (10) days following the expiration of the
restoration deadline.

          D.   In any of the aforesaid circumstances, rental shall abate
proportionately during the period and to the extent that the Leased Premises are
unfit for use by Tenant in the ordinary conduct of Tenant's business. In the
event that this Lease is terminated as herein permitted, Landlord shall refund
to Tenant the prepaid rental (unaccrued as of the date of damage or destruction)
less any sum then owing Landlord by Tenant. If this Lease continues, then the
Term of this Lease shall be extended by a period of time equal to the period of
such repair and reconstruction. Any insurance which may be carried by Landlord
or Tenant against loss or damage to the Building or to the Leased Premises shall
be for the sole benefit of the party carrying such insurance under its control,
and it is understood that Landlord shall in no event be obligated to carry
insurance on Tenant's contents.

     9.   COMPLIANCE WITH LAWS AND USAGE. Tenant, at Tenant's own expense, (a)
shall comply with all federal, state, municipal, fire underwriting and other
laws, ordinances, orders, rules and regulations applicable to the Leased
Premises and the business conducted therein by Tenant, (b) shall not engage in
any activity which would cause Landlord's fire and extended coverage insurance
to be canceled or the rate therefor to be increased (or, at Landlord's option,
Tenant shall pay any such increase to Landlord immediately upon demand as
additional rental in the event of such rate increase by reason of such
activity), (c) shall not commit, and shall cause Tenant's agents, employees and
invitees not to commit, any act which is a nuisance or unreasonable annoyance to
Landlord or to other tenants, or which might, in the reasonable judgment of
Landlord, damage Landlord's goodwill or reputation, or tend to unreasonably
injure or depreciate the Building, (d) shall not commit or permit waste in the
Leased Premises or the Building, (e) shall comply with rules and regulations
from time to time reasonably promulgated by Landlord applicable to the Leased
Premises and/or the Building, (f) shall not paint, erect or display any sign,
advertisement, placard or lettering which is visible in the corridors or lobby
of the Building or from the exterior of the Building without Landlord's prior
written approval, and (g) shall not occupy or use, or permit any portion of
the Leased Premises to be occupied or used, for any business or purpose other
than the Permitted Use specified in Paragraph 1.O. hereof. If a controversy
arises concerning Tenant's compliance with any federal, state, municipal or
other laws, ordinances, orders, rules or regulations applicable to the Leased
Premises and the business conducted therein by Tenant, Landlord may retain
independent consultants of recognized standing to investigate Tenant's
compliance. If it is determined by such independent consultant that Tenant has
not complied as required, Tenant shall reimburse Landlord on demand for all
actual and reasonable consulting and other costs incurred by Landlord in such
investigation. Landlord and Tenant acknowledge that, in accordance with the
provisions of the Americans with Disabilities Act of 1990 and the Texas
Elimination of Architectural Barriers Act, each as amended from time to time,
and all regulations and guidelines issued by authorized agencies with respect
thereto (collectively, the "ADA" and the "EAB", respectively), responsibility
for compliance with the terms and conditions of Title III of the ADA and the EAB
may be allocated as between Landlord and Tenant. Notwithstanding anything to the
contrary contained in the Lease, Landlord and Tenant agree that the
responsibility for compliance with the ADA and the EAB shall be allocated as
follows: (i) Tenant shall be responsible for compliance with the provisions of
Title III of the ADA and with the provisions of the EAB with respect to the
Leased Premises, including restrooms within the Leased Premises, and (ii)
Landlord shall be responsible for compliance with the provisions of Title III of
the ADA and with the provisions of the EAB with respect to the exterior of the
Building, parking areas, sidewalks and walkways, and any and all areas
appurtenant thereto, together with all common areas of the Building not included
within the Leased Premises. The allocation of responsibility for ADA and EAB
compliance between Landlord and Tenant, and the obligations of Landlord and
Tenant established by such allocations, shall supersede any other provisions of
the Lease that may contradict or otherwise differ from the requirements of this
paragraph.

     10.  LIABILITY AND INDEMNITY.

          A.   Tenant agrees to indemnify and save Landlord harmless from all
third-party claims (including costs and expenses of defending against such
claims) arising or alleged to arise from any negligent act or omission or
willful misconduct of Tenant or Tenant's agents, employees, or contractors.
Landlord agrees to indemnify and save Tenant harmless from all third-party
claims (including costs and expenses of defending against such claims) arising
or alleged to arise from any negligent act or omission or willful misconduct of
Landlord or Landlord's agents, employees or contractors.

          B.   Notwithstanding any provision in this Lease to the contrary,
Landlord and Tenant each hereby waives any and all rights of recovery, claim,
action, or cause of action, against the other, its agents, officers, or
employees, for any loss or damage that may occur to the Leased Premises, or
any improvements thereto, or the Building of which the Leased Premises are a
part, or any improvements thereto, or any personal property of such party,
therein, by reason of fire, the elements, or any other cause which is or
would be insured against under the terms of the property insurance policies
carried or required to be carried under the terms of this Lease by the
respective parties hereto, regardless of cause or origin, including
negligence of the other party hereto, its agents, officers, or employees, and
covenants that no insurer shall hold any right of subrogation against such
other party (and all such insurance policies shall be amended or endorsed to
reflect such waiver of subrogation). This waiver of subrogation provision
shall be effective to the full extent, but only to the extent that it does
not impair the effectiveness of insurance policies of Landlord and Tenant.

                                     -6-



          C.   Tenant, to the extent permitted by law, waives all claims Tenant
may have against Landlord, and against Landlord's agents and employees for
injury to person or damage to or loss of property sustained by Tenant or by any
occupant of the Leased Premises, or by any other person, resulting from any part
of the Building or any equipment or appurtenances becoming out of repair, or
resulting from any accident in or about the Building or resulting directly or
indirectly from any act or neglect of any tenant or occupant of any part of the
Building or of any other person, unless such damage is a result of the
negligence or willful misconduct of Landlord, or Landlord's agents or employees
or Landlord's default in the performance of its obligations under this Lease. If
any damage results from any act or neglect of Tenant and if the cost of repair
of such damage would not be covered by a fire and extended coverage insurance
policy maintained by Landlord on the Project, then Landlord may, at Landlord's
option, repair such damage, and Tenant shall thereupon pay to Landlord the total
cost of such repair. All personal property belonging to Tenant or any occupant
of the Leased Premises that is in or on any part of the property belonging to
Tenant or any occupant of the Leased Premises that is in or on any part of the
Building shall be there at the risk of Tenant or of such other person only, and
Landlord, Landlord's agents and employees shall not be liable for any damage
thereto or for the theft or misappropriation thereof unless such damage, theft
or misappropriation is a result of the negligence or willful misconduct of
Landlord or Landlord's agents or employees.

     11.  ADDITIONS AND FIXTURES.

          A.   Tenant will make no alteration, change, improvement, repair,
replacement or physical addition in or to the Leased Premises without the prior
written consent of Landlord which consent shall not be unreasonably withheld. If
such prior written consent of Landlord is granted, the work in such connection
shall be at Tenant's expense but by workmen of Landlord or by workmen and
contractors reasonably approved in advance in writing by Landlord and in a
manner and upon terms and conditions and at times satisfactory to and approved
in advance in writing by Landlord. In any instance where Landlord grants such
consent, Landlord may grant such consent contingent and conditioned upon
Tenant's contractors, laborers, materialmen and others furnishing labor or
materials for Tenant's job working in harmony and not interfering with any labor
utilized by Landlord, Landlord's contractors or mechanics or by any other tenant
or such other tenant's contractors or mechanics; and if at any time such entry
by one (1) or more persons furnishing labor or materials for Tenant's work shall
cause disharmony or interference for any reason whatsoever without regard to
fault, the consent granted by Landlord to Tenant may be withdrawn at any time
upon written notice to Tenant.

          B.   Tenant, if Tenant so elects, may remove Tenant's trade fixtures,
office supplies and movable office furniture and equipment not attached to the
Building provided (i) such removal is made prior to the expiration of the Term
of this Lease, (ii) Tenant is not in default of any obligation or covenant under
this Lease at the time of such removal, and (iii) Tenant promptly repairs all
damage caused by such removal. All other property at the Leased Premises and any
alteration or addition to the Leased Premises (including wall-to-wall carpeting,
paneling or other wall covering) and any other article attached or affixed to
the floor, wall or ceiling of the Leased Premises shall become the property of
Landlord shall be in good condition, normal wear and tear excepted, and shall
remain upon and be surrendered with the Leased Premises as part thereof at the
expiration of the Term of this Lease, Tenant hereby waiving all rights to any
payment or compensation therefor. If, however, Landlord so requests in writing,
Tenant will, prior to the termination of this Lease, remove in a good and
workmanlike manner any and all alterations, additions, fixtures, equipment and
property placed or installed by Tenant in the Leased Premises and will repair
any damage occasioned by such removal.

     12.  ASSIGNMENT AND SUBLETTING.

          A.   Neither Tenant nor Tenant's legal representatives or
successors in interest by operation of law or otherwise shall assign this
Lease or sublease the Leased Premises or any part thereof or mortgage, pledge
or hypothecate its leasehold interest or grant any concession or license
within the Leased Premises without the prior express written permission of
Landlord, which permission shall not be unreasonably withheld, and any
attempt to do any of the foregoing without the prior express written
permission of Landlord shall be void and of no effect. In determining whether
to grant permission to Tenant's request to assign this lease or sublease the
Leased Premises, Landlord may consider any reasonable factor. Landlord and
Tenant agree that any one of the following factors, or any other reasonable
factor, will be reasonable grounds for deciding Tenant's request:

               (i)     The business reputation of the proposed assignee or
          sublessee must be in accordance with generally acceptable commercial
          standards and consistent with a class A office building environment;

               (ii)    The use of the Leased Premises by the proposed assignee
          or sublessee must be only for the use permitted under this Lease;

               (iii)   The proposed assignee or sublessee may not be a tenant or
          occupant in the Building, unless (a) such tenant or occupant is then
          leasing premises on the same floor of the Building as Tenant or on a
          floor immediately above or below the Leased Premises, and (b) the
          Building is at least 95% leased; and

               (iv)    The use of the Leased Premises by the proposed assignee
          or sublessee shall not violate any other agreements affecting the
          Leased Premises, the Building, Landlord or other tenants.


                                         -7-



In the event Tenant requests Landlord's prior express permission as to any such
assignment, sublease or other transaction, Landlord shall have the right and
option, as of the requested effective date of such assignment, sublease or other
transaction (but no obligation), to cancel and terminate this Lease as to the
portion of the Leased Premises with respect to which Landlord has been requested
to permit such assignment, sublease or other transaction, and if Landlord elects
to cancel and terminate this Lease as to the aforesaid portion of the Leased
Premises, then the rental and other charges payable hereunder shall thereafter
be proportionately reduced. In the event of any such attempted assignment or
attempted sublease, or should Tenant, in any other nature of transaction, permit
or attempt to permit anyone to occupy the Leased Premises (or any portion
thereof) without the prior express written permission of Landlord, Landlord
shall thereupon have the right and option to cancel and terminate this Lease
effective upon ten (10) days' notice to Tenant given by Landlord at any time
thereafter either as to the entire Leased Premises or as to only the portion
thereof which Tenant shall have attempted to assign or sublease or otherwise
permitted some other party's occupancy without Landlord's prior express written
permission, and if Landlord elects to cancel and terminate this Lease as to the
aforesaid portion of the Leased Premises, then the rental and other charges
payable hereunder shall thereafter be proportionately reduced. This prohibition
against assignment or subletting shall be construed to include a prohibition
against any assignment or subletting by operation of law.

          B.   Notwithstanding that the prior express written permission of
Landlord to any of the aforesaid transactions may have been obtained, the
following shall apply:

          (1)  In the event of an assignment, contemporaneously with the
     granting of Landlord's aforesaid consent, Tenant shall cause the assignee
     to expressly assume in writing and agree to perform all of the covenants,
     duties and obligations of Tenant hereunder, and such assignee shall be
     jointly and severally liable therefor along with Tenant; Tenant shall
     further cause such assignee to grant Landlord an express first and prior
     contract lien and security interest in the manner hereinafter stated as
     applicable to Tenant;

          (2)  A signed counterpart of all instruments relative thereto
     (executed by all parties to such transactions with the exception of
     Landlord) shall be submitted by Tenant to Landlord prior to or
     contemporaneously with the request for Landlord's prior express written
     permission thereto (it being understood that no such instrument shall be
     effective without the prior express written permission of Landlord);

          (3)  Tenant shall subordinate to Landlord's statutory lien and
     Landlord's aforesaid contract lien and security interest any liens or other
     rights which Tenant may claim with respect to any fixtures, equipment,
     goods, wares, merchandise or other property owned by or leased to the
     proposed assignee or sublessee or other party intending to occupy the
     Leased Premises;

          (4)  No usage of the Leased Premises different from the usage herein
     provided to be made by Tenant shall be permitted, and all other terms and
     provisions of this Lease shall continue to apply after any such
     transaction;

          (5)  In any case where Landlord consents to an assignment, sublease,
     grant of a concession or license or mortgage, pledge or hypothecation of
     the leasehold, the undersigned Tenant will nevertheless remain directly and
     primarily liable for the performance of all of the covenants, duties and
     obligations of Tenant hereunder (including, without limitation, the
     obligation to pay all rental and other sums herein provided to be paid),
     and Landlord shall be permitted to enforce the provisions of this Lease
     against the undersigned Tenant and/or any assignee, sublessee,
     concessionaire, licensee or other transferee without demand upon or
     proceeding in any way against any other person; and

          (6)  If the rental due and payable by a sublessee under any such
     permitted sublease (or a combination of the rental payable under such
     sublease plus any bonus or other consideration therefor or incident
     thereto) exceeds the hereinabove provided rental payable under this Lease,
     or if with respect to a permitted assignment, permitted license or other
     transfer by Tenant permitted by Landlord, the consideration related to the
     Lease payable to Tenant by the assignee, licensee or other transferee
     exceeds the rental payable under this Lease, then Tenant shall be bound and
     obligated to pay Landlord all such excess rental and other excess
     consideration within ten (10) days following receipt thereof by Tenant from
     such sublessee, assignee, licensee or other transferee, as the case might
     be.

          C.   If Tenant is a corporation, then any transfer of this Lease from
Tenant by merger, consolidation or dissolution or any change in ownership or
power to vote a majority of the voting stock in Tenant outstanding at the time
of execution of this Lease shall constitute an assignment for the purpose of
this Lease; provided, however, that acquisition of all stock of a corporate
tenant by any corporation, the stock of which is registered pursuant to the
Securities Act of 1933 or the merger of a corporate tenant into such a
corporation, the stock of which is so registered, shall not itself be deemed to
be a violation of Paragraph 12.A. For purposes of this Paragraph 12.C., the term
"voting stock" shall refer to shares of stock regularly entitled to vote for the
election of directors of the corporation involved.


                                      -8-



          If Tenant is a general partnership having one (1) or more corporations
as partners or if Tenant is a limited partnership having one (1) or more
corporations as general partners, the provisions of the preceding paragraph of
this Paragraph 12.C. shall apply to each of such corporations as if such
corporation alone had been the Tenant hereunder.

          If Tenant is a general partnership (whether or not having any
corporations as partners) or if Tenant is a limited partnership (whether or not
having any corporations as general partners), the transfer of the partnership
interest or interests constituting a majority shall constitute an assignment for
the purposes of this Lease.

          D.   Consent by Landlord to a particular assignment or sublease or
other transaction shall not be deemed a consent to any other or subsequent
transaction. If this Lease is assigned, or if the Leased Premises are subleased
(whether in whole or in part), or in the event of the mortgage, pledge or
hypothecation of the leasehold interest or grant of any concession or license
within the Leased Premises without the prior express written permission of
Landlord, or if the Leased Premises are occupied in whole or in part by anyone
other than Tenant without the prior express written permission of Landlord, then
Landlord may nevertheless collect rental and other charges from the assignee,
sublessee, mortgagee, pledgee, party to whom the leasehold interest was
hypothecated, concessionaire or licensee or other occupant and apply the net
amount collected to the rental and other charges payable hereunder, but no such
transaction or collection of rental and other charges or application thereof by
Landlord shall be deemed a waiver of these provisions or a release of Tenant
from the further performance by Tenant of Tenant's covenants, duties and
obligations hereunder.

          E.   Notwithstanding anything to the contrary herein, an assignment of
the Lease shall not include, and the terms of Paragraph 12 of the Lease shall
not apply to, (i) a transfer of the Lease to an entity which is the parent of
Tenant, subsidiary of Tenant, affiliate of Tenant, or shall directly or
indirectly control, be controlled by or be under common control with Tenant;
(ii) a transaction in which Tenant becomes an entity whose shares of stock or
other ownership interests are, directly or indirectly, sold on a national stock
exchange or an inter-dealer quotation system; (iii) in the event the transaction
described in clause (ii) above shall have occurred, any subsequent sale of
ownership interests or issuance of new ownership interests, directly or
indirectly, in Tenant; and (iv) a transaction in which any entity succeeds to
all or substantially all of the assets of Tenant whether by merger, sale or
otherwise provided such successor entity has had substantial experience in the
operation of Tenant's business and assumes in full the obligations of Tenant
under this Lease; provided, however, that (i) Tenant shall remain liable for the
performance of all covenants, duties and obligations under the Lease,
irrespective of any such assignment, (ii) the use of the Leased Premises by the
assignee may not violate any other agreements affecting the Leased Premises, the
Building, Landlord or other tenants, and (iii) use of the Leased Premises by the
assignee shall conform with the uses permitted by this Lease. Tenant shall
notify Landlord, in writing, of any such assignment or sublease within ninety
(90) days of its occurrence and shall provide Landlord with all such reasonable
information as Landlord may request regarding the identity and status of such
assignee.

          F.   Landlord acknowledges that the business to be conducted by the
undersigned Tenant in the Leased Premises requires the installation of certain
communications equipment owned by customers and co-locators of the undersigned
Tenant ("Permitted Licensees") in (but not outside of) the Leased Premises, in
order for the Permitted Licensees to interconnect with Tenant's facilities. To
expedite the Permitted Licensees' access to the Leased Premises, Landlord
expressly agrees that Tenant may license the use of portions of the Leased
Premises to, or enter into other co-location agreements (collectively,
"Permitted Agreements") with, the Permitted Licensees without Landlord's further
consent. Landlord expressly waives its right to prior review of such Permitted
Agreements; provided, however, that Tenant shall promptly provide Landlord with
copies of all such Permitted Agreements and shall accede to Landlord's
reasonable requests, if any, as to floor plans and space layout. In addition,
Landlord expressly waives any right it may have to terminate this Lease or any
portion hereof as set forth in Paragraph 12.A. above with respect to such
Permitted Agreements. Paragraph 12.B.(6), 12.C. and 12.D. above shall not apply
with respect to Tenant's Permitted Agreements with Permitted Licensees.
Notwithstanding anything herein to the contrary, Tenant's Permitted Agreements
with the Permitted Licensees may not affect the Building's riser facilities or
the Common Area of the Building.

     13.  SUBORDINATION. Tenant accepts this Lease subject and subordinate to
any ground lease, mortgage, deed of trust or other lien presently existing or
hereafter placed upon the Leased Premises or upon the Building or any part
thereof, and to any renewals, modifications, extensions and refinancings
thereof, which might now or hereafter constitute a lien upon the Building or any
part thereof, and to zoning ordinances and other building and fire ordinances
and governmental regulations relating to the use of the Leased Premises, but
Tenant agrees that any such ground lessor, mortgagee and/or beneficiary of any
deed of trust or other lien ("Landlord's Mortgagee") and/or Landlord shall have
the right at any time to subordinate such ground lease, mortgage, deed of trust
or other lien to this Lease on such terms and subject to such conditions as such
Landlord's Mortgagee may deem appropriate in its discretion. Upon demand Tenant
agrees to execute such further instruments subordinating this Lease, as Landlord
may request, and such nondisturbance and attornment agreements, as any such
Landlord's Mortgagee shall request, in form satisfactory to Landlord's Mortgagee
and Tenant. Upon foreclosure of the Building or upon acceptance of a deed in
lieu of such foreclosure, Tenant hereby agrees to attorn to the new owner of
such property after such foreclosure or acceptance of a deed in lieu of
foreclosure, if so requested by such new owner of the Building. Notwithstanding
any contrary provision contained herein, the subordination of this Lease to
any mortgage deed of trust or other lien hereafter placed upon the Leased
Premises or the Building or any part thereof and Tenant's


                                      -9-



agreement to attorn to the holder of such mortgage, deed of trust or other lien
as provided in this Paragraph 13 shall be conditioned upon such holder's
entering into a non-disturbance and attornment agreement mutually acceptable to
Tenant and Landlord's Mortgagee.

     14.  OPERATING EXPENSES.

          A.   For purposes of this Paragraph 14, the following definitions and
     calculations shall apply:

          (1)  The term "Operating Expenses" shall mean all reasonable expenses,
     costs and disbursements of every kind and nature which Landlord shall pay
     or become obligated to pay because of or in connection with the ownership,
     operation, maintenance, repair, replacement, protection and security of the
     Project, determined on an accrual basis in accordance with generally
     accepted accounting principles, including, without limitation, the
     following:

               (i)     Salaries and wages of all employees engaged in the
          operation, maintenance and security of the Project, including taxes,
          insurance and benefits (including pension, retirement and fringe
          benefits) relating thereto;

               (ii)    Cost of all supplies and materials used in the operation,
          maintenance and security of the Project;

               (iii)   Cost of all water and sewage service supplied to the
          Project;

               (iv)    Cost of all maintenance and service agreements for the
          Project and the equipment therein, including, without limitation,
          alarm service, parking facilities, security (both on-site and
          off-site), janitorial service, landscaping, fire protection,
          sprinklers, window cleaning and elevator maintenance;

               (v)     Cost of all insurance relating to the Project, including
          the cost of casualty, rental and liability insurance applicable to the
          Project and Landlord's personal property used in connection
          therewith;

               (vi)    All taxes, assessments and governmental charges (foreseen
          or unforeseen, general or special, ordinary or extraordinary) whether
          federal, state, county or municipal and whether levied by taxing
          districts or authorities presently taxing the Project or by others
          subsequently created or otherwise, and any other taxes and assessments
          attributable to the Project or its operation, and all taxes of
          whatsoever nature that are imposed in substitution for or in lieu of
          any of the taxes, assessments or other charges herein defined;
          provided, however, Operating Expenses shall not include taxes paid by
          tenants of the Project as a separate charge on the value of their
          leasehold improvements, death taxes, excess profits taxes, franchise
          taxes and state and federal income taxes;

               (vii)   Cost of repairs and general maintenance, including,
          without limitation, reasonable depreciation charges applicable to all
          equipment used in repairing and maintaining the Project, but
          specifically excluding repairs and general maintenance paid by
          proceeds of insurance or by Tenant or by other third parties;

               (viii)  Cost of capital improvement items, including installation
          thereof, which are acquired primarily for the purpose of reducing
          Operating Expenses; and

               (ix)    Reasonable management fees paid by Landlord to third
          parties or to management companies owned by, or management divisions
          of, Landlord, not to exceed the then prevailing market rate for the
          management of high quality class A office buildings comparable to the
          Project.

               To the extent that any Operating Expenses are attributable to the
     Project and other projects of Landlord, a fair and reasonable allocation of
     such Operating Expenses shall be made between the Project and such other
     projects.

          (2)  The term "Operating Expenses" shall exclude the cost of
     electrical energy supplied to the Project and to tenants of the Building.

          (3)  The term "Base Operating Expenses Rate" is stipulated to be the
     rate specified in Paragraph 1.T. hereof per square foot of rentable area in
     the Leased Premises.

          (4)  The term "Actual Operating Expenses" shall mean, with respect to
     each calendar year during the Term of this Lease, the actual Operating
     Expenses for such year. The term "Actual Operating Expenses Rate" shall
     mean, with respect to each calendar year during the Term of this Lease, the
     Actual Operating Expenses attributable to each square foot of rentable area
     in the Building, and shall be calculated by dividing the Actual Operating
     Expenses by the total number of square feet of rentable area in the
     Building, as specified in Paragraph 1.I. hereof. The term "Tenant's
     Proportionate Share of Actual Operating Expenses" shall mean,


                                      -10-





     with respect to each calendar year during the Term of this Lease, an amount
     equal to the product of (i) the positive difference (if any) obtained by
     subtracting the Base Operating Expenses Rate from the Actual Operating
     Expenses Rate, multiplied by (ii) the weighted average number of square
     feet of rentable area in the Leased Premises in such year; provided,
     however, if the Actual Operating Expenses Rate is determined on the basis
     of a partial calendar year, then in making the foregoing calculation, the
     Base Operating Expenses Rate shall be multiplied by a fraction, the
     numerator of which is the number of days in such partial calendar year and
     the denominator of which is 365, and the foregoing weighted average shall
     be calculated only on the basis of the portion of such calendar year
     covered by the Term of this Lease.

          For example, if the Actual Operating Expenses Rate for a calendar year
     is $3.20 and the Base Operating Expenses Rate is $3.00, and the Leased
     Premises contains 19,000 square feet of rentable area during the entire
     calendar year, Tenant's Proportionate Share of Actual Operating Expenses is
     $3,800.00, calculated as follows: ($3.20 - $3.00) x 19,000 = $3,800.00.

          B.   If the Actual Operating Expenses Rate during any calendar year is
greater than the Base Operating Expenses Rate, Tenant shall be obligated to pay
to Landlord as additional rental an amount equal to Tenant's Proportionate Share
of Actual Operating Expenses. To implement the foregoing, Landlord shall provide
to Tenant within ninety (90) days (or as soon thereafter as reasonably possible)
after the end of the calendar year in which the Commencement Date occurs, a
reasonably detailed statement of the Actual Operating Expenses for such calendar
year, the Actual Operating Expenses Rate for such calendar year, and Tenant's
Proportionate Share of Actual Operating Expenses. If the Actual Operating
Expenses Rate for such calendar year exceeds the Base Operating Expenses Rate,
Tenant shall pay to Landlord, within thirty (30) days after Tenant's receipt of
such statement, an amount equal to Tenant's Proportionate Share of Actual
Operating Expenses for such calendar year.

          C.   Beginning with the Commencement Date of this Lease (or as soon
thereafter as reasonably possible), Landlord shall provide to Tenant a statement
of the projected annual Operating Expenses per square foot of rentable area in
the Project (the "Projected Operating Expenses Rate"). Tenant shall pay to
Landlord on the first day of each month an amount (the "Projected Operating
Expenses Installment") equal to one-twelfth (1/12) of the product of (i) the
positive difference (if any) obtained by subtracting the Base Operating Expenses
Rate from the Projected Operating Expenses Rate for such calendar year,
multiplied by (ii) the number of square feet of rentable area in the Leased
Premises on the first day of the prior month. Until Tenant has received the
statement of the Projected Operating Expenses Rate from Landlord, Tenant shall
continue to pay Projected Operating Expenses Installments to Landlord in the
same amount (if any) as required for the last month of the prior calendar year.
Upon Tenant's receipt of such statement of the Projected Operating Expenses
Rate, Tenant shall pay to Landlord, or Landlord shall pay to Tenant (whichever
is appropriate), the difference between the amount paid by Tenant prior to
receiving such statement and the amount payable by Tenant as set forth in such
statement. Landlord shall provide Tenant a statement within ninety (90) days (or
as soon thereafter as reasonably possible) after the end of each calendar year,
showing the Actual Operating Expenses Rate as compared to the Projected
Operating Expenses Rate for such calendar year. If Tenant's Proportionate Share
of Actual Operating Expenses for such calendar year exceeds the aggregate of the
Projected Operating Expenses Installments collected by Landlord from Tenant,
Tenant shall pay to Landlord, within thirty (30) days following Tenant's receipt
of such statement, the amount of such excess. If Tenant's Proportionate Share of
Actual Operating Expenses for such calendar year is less than the aggregate of
the Projected Operating Expenses Installments collected by Landlord from Tenant,
Landlord shall pay to Tenant, within thirty (30) days following Tenant's receipt
of such statement, the amount of such excess. Landlord shall have the right from
time to time during each calendar year to revise the Projected Operating
Expenses Installments on the basis of the revised statement. If the Commencement
Date of this Lease is not the first day of a calendar year, or the expiration or
termination date of this Lease is not the last day of a calendar year, then
Tenant's Proportionate Share of Actual Operating Expenses shall be prorated. The
foregoing adjustment provisions shall survive the expiration or termination of
the Term of this Lease.

          D.   Notwithstanding any other provision herein to the contrary, it is
agreed that if the Project is less than 95% occupied during any calendar year an
adjustment shall be made in computing the Actual Operating Expenses for such
year so that the Actual Operating Expenses are computed as though the Project
had been 95% occupied during such year. In no event shall the operation of this
provision of the Lease result in the recovery from the Building tenants of more
than 100% of the excess of the Operating Expenses in any one calendar year over
such tenants' base stops or year(s). Such gross-up clause only applies to
Operating Expenses which fluctuate in relation to the occupancy of the Building.

          E.   Landlord agrees to keep books and records reflecting the
Operating Expenses of the Project in accordance with generally accepted
accounting principles. Tenant, at its expense, shall have the right, within six
(6) months after receiving Landlord's statement of Actual Operating Expenses for
a particular year, to audit Landlord's books and records relating to the
Operating Expenses for such year if the Actual Operating Expenses Rate exceeds
the Base Operating Expenses Rate; or, at Landlord's sole option, Landlord may
provide such audit prepared by a certified public accountant selected by
Landlord. If conducted by Tenant, such audit shall be conducted only during
regular business hours at Landlord's office and only after Tenant gives Landlord
fourteen (14) days written notice. Tenant shall deliver to Landlord a copy of
the results of such audit within fifteen (15) days of its receipt by Tenant. No
such audit shall be conducted if any other tenant has conducted an audit for the
time period Tenant intends to audit and Landlord furnishes to Tenant a copy of
the results of such audit. No audit


                                      -11-



shall be conducted at any time that Tenant is in default of any of terms of the
lease. No subtenant shall have any right to conduct an audit and no assignee
shall conduct an audit for any period during which such assignee was not in
possession of the Leased Premises. Such audit must be conducted by an
independent nationally recognized accounting firm that is not being compensated
by Tenant on a contingency fee basis. All information obtained through the
Tenant's audit with respect to financial matters (including, without limitation,
costs, expenses, income) and any other matters pertaining to the Landlord and/or
the Project as well as any compromise, settlement, or adjustment reached between
Landlord and Tenant relative to the results of the audit shall be held in strict
confidence by the Tenant and its officers, agents, and employees; and Tenant
shall cause its auditor and any of its officers, agents, and employees to be
similarly bound. As a condition precedent to Tenant's exercise of its right to
audit, Tenant must deliver to Landlord a signed covenant from the auditor in a
form reasonably satisfactory to Landlord acknowledging that all of the results
of such audit as well as any compromise, settlement, or adjustment reached
between Landlord and Tenant shall be held in strict confidence and shall not be
revealed in any manner to any person except upon the prior written consent of
Landlord, which consent may be withheld in Landlord's sole discretion, or if
required pursuant to any litigation between Landlord and Tenant materially
related to the facts disclosed by such audit, or if required by law. Tenant
understands and agrees that this provision is of material importance to Landlord
and that any violation of the terms of this provision shall result in immediate
and irreparable harm to Landlord. Landlord shall have all rights allowed by law
or equity if Tenant, its officers, agents, or employees and/or the auditor
violate the terms of this provision, including, without limitation, the right to
terminate this Lease or the right to terminate Tenant's right to audit in the
future pursuant to this paragraph. Tenant shall indemnify, defend upon request,
and hold Landlord harmless from and against all costs, damages, claims,
liabilities, expenses, losses, court costs, and attorneys' fees suffered by or
claimed against Landlord, based in whole or in part upon the breach of this
paragraph by Tenant and/or its auditor, and shall cause its auditor to be
similarly bound. If within such six (6) month period Tenant does not give
Landlord written notice stating in reasonable detail any objection to the
statement of Actual Operating Expenses, Tenant shall be deemed to have approved
such statement in all respects.

     15.  EMINENT DOMAIN. If there shall be taken by exercise of the power of
eminent domain during the Term of this Lease any part of the Leased Premises or
the Building, Landlord may elect to terminate this Lease or to continue same in
effect if any one of the following conditions is met or circumstances apply:

               (i)     such event shall occur in the last twelve (12) months of
          the Term of the Lease;

               (ii)    the mortgagee under any mortgage or deed of trust
          covering the Building shall require that condemnation proceeds payable
          as a result of such event be withheld and applied against the mortgage
          debt, and the necessary repair and restoration of the Leased Premises
          and/or the Building would cost in excess of $500,000.00; or

               (iii)   all other leases in the Building are terminated as a
          result of such event.

If there shall be taken by exercise of the power of eminent domain any part of
the Leased Premises or the Building which materially affects Tenant's ability to
conduct its operations in the Leased Premises, then Tenant shall have the right
to terminate this Lease upon thirty (30) days' written notice to Landlord
following such taking. If this Lease continues, the rental shall be reduced in
proportion to the area of the Leased Premises so taken, and Landlord shall
repair any damage to the Leased Premises or the Building resulting from such
taking. All sums awarded or agreed upon between Landlord and the condemning
authority for the taking of the interest of Landlord or Tenant, whether as
damages or as compensation, will be the property of Landlord without prejudice,
however, to claims of Tenant against the condemning authority on account of the
unamortized cost of leasehold improvements paid for by Tenant taken by the
condemning authority. If this Lease should be terminated under any provision of
this Paragraph 15, rental shall be payable up to the date that possession is
taken by the condemning authority, and Landlord will refund to Tenant any
prepaid unaccrued rental less any sum then owing by Tenant to Landlord.

     16.  ACCESS BY LANDLORD. Landlord, Landlord's agents and employees shall
have access to and the right to enter upon any and all parts of the Leased
Premises at any reasonable time after reasonable prior notice, which notice
may be oral or written (except in cases of emergency, defined to be any
situation in which Landlord perceives imminent danger of injury to person
and/or damage to or loss of property, in which case Landlord may enter upon
any and all parts of the Leased Premises at any time) to examine the
condition thereof, to clean, to make any repairs, alterations or additions
required to be made by Landlord hereunder, to show the Leased Premises to
prospective purchasers or tenants or mortgage lenders (prospective or
current) and for any other purpose deemed reasonable by Landlord, and Tenant
shall not be entitled to any abatement or reduction of rental by reason
thereof.
      17.  LANDLORD'S LIEN. The parties agree that during the Term of this
Lease Tenant's cabling, conduits and other connecting equipment, including
without limitation the equipment and items described in Paragraph 32 of the
Lease (collectively, "Connecting Equipment"), the supplemental air
conditioner installed by Tenant and all of the telecommunications equipment
in the Leased Premises shall be deemed the property of Tenant, and not
fixtures of the Building. Landlord hereby waives its rights, statutory or
otherwise, to any lien on the telecommunications  equipment in the Leased
Premises, the supplemental air conditioner installed by Tenant and the
Connecting Equipment. At the end of the term of the Lease, Tenant may, at its
election, or shall, if requested

                                      -12-




by Landlord, remove all of Tenant's telecommunication equipment, supplemental
air conditioner installed by Tenant and the Connecting Equipment in a safe and
workmanlike manner.

     18. DEFAULTS.

          A.   Each of the following acts or omissions of Tenant or occurrences
shall constitute an "Event of Default":

          (1)  Failure or refusal by Tenant to pay rental or other payments
     hereunder upon the expiration of a period of ten (10) days following
     written notice to Tenant of such failure.

          (2)  Failure to perform or observe any covenant or condition of this
     Lease by Tenant to be performed or observed upon the expiration of a period
     of ten (10) days following written notice to Tenant of such failure;
     provided, however, that in the event Tenant's failure to perform a covenant
     or condition of this Lease cannot reasonably be cured within ten (10) days
     following written notice to Tenant, Tenant shall not be in default if
     Tenant commences to cure same within the ten (10) day period and thereafter
     diligently prosecutes the curing thereof.

          (3)  The filing or execution or occurrence of any one of the
     following: (i) a petition in bankruptcy or other insolvency proceeding by
     or against Tenant, (ii) petition or answer by Tenant seeking relief under
     any provision of the Bankruptcy Act, (iii) an assignment for the benefit of
     creditors or composition, (iv) a petition or other proceeding by or against
     Tenant for the appointment of a trustee, receiver or liquidator of Tenant
     or any of Tenant's property, or (v) a proceeding by any governmental
     authority for the dissolution or liquidation of Tenant. Notwithstanding the
     foregoing, Tenant shall have one hundred twenty (120) days to obtain a
     dismissal of an involuntary bankruptcy proceeding or other involuntary
     proceeding before such an event shall constitute an Event of Default.

          B.   This Lease and the Term and estate hereby granted and the demise
hereby made are subject to the limitation that if and whenever any Event of
Default shall occur, Landlord may, at Landlord's option, in addition to all
other rights and remedies given hereunder or by law or equity, do any one (1) or
more of the following:

          (1)  Terminate this Lease, in which event Tenant shall immediately
     surrender possession of the Leased Premises to Landlord.

          (2)  Enter upon and take possession of the Leased Premises and expel
     or remove Tenant and any other occupant therefrom, with or without having
     terminated the Lease.

          (3)  Alter locks and other security devices at the Leased Premises.

          C.   Exercise by Landlord of any one (1) or more remedies hereunder
granted or otherwise available shall not be deemed to be an acceptance of
surrender of the Leased Premises by Tenant, whether by agreement or by operation
of law, it being understood that such surrender can be effected only by the
written agreement of Landlord and Tenant. No such alteration of security devices
and no removal or other exercise of dominion by Landlord over the property of
Tenant or others at the Leased Premises shall be deemed unauthorized or
constitute a conversion, Tenant hereby consenting, after any Event of Default,
to the aforesaid exercise of dominion over Tenant's property within the
Building. All claims for damages by reason of such re-entry and/or possession
and/or alteration of locks or other security devices are hereby waived, as are
all claims for damages by reason of any distress warrant, forcible detainer
proceedings, sequestration proceedings or other legal process. Tenant agrees
that any re-entry by Landlord may be pursuant to judgment obtained in forcible
detainer proceedings or other legal proceedings or without the necessity for any
legal proceedings, as Landlord may elect, and Landlord shall not be liable in
trespass or otherwise.

          D.   In the event that Landlord elects to terminate this Lease by
reason of an Event of Default, then, notwithstanding such termination, Tenant
shall be liable for and shall pay to Landlord, at the address specified in
Paragraph 1.C. hereof, the sum of all rental and other indebtedness accrued to
the date of such termination, plus, as damages, an amount equal to the then
present value of the rental reserved hereunder for the remaining portion of the
Term of this Lease (had such Term not been terminated by Landlord prior to the
expiration of the Term of this Lease), less the then present value of the fair
rental value of the Leased Premises for such period.

          In the event that Landlord elects to terminate the Lease by reason of
an Event of Default, in lieu of exercising the rights of Landlord under the
preceding paragraph of this Paragraph 18.D., Landlord may instead hold Tenant
liable for all rental and other indebtedness accrued to the date of such
termination, plus such rental and other indebtedness as would otherwise have
been required to be paid by Tenant to Landlord during the period following
termination of the Term of this Lease measured from the date of such termination
by Landlord until the expiration of the Term of this Lease (had Landlord not
elected to terminate the Lease on account of such Event of Default) diminished
by any net sums thereafter received by Landlord through reletting the Leased
Premises during said period (after deducting expenses incurred by Landlord as
provided in Paragraph 18.F. hereof). Actions to collect amounts due by Tenant
provided for in this paragraph of this Paragraph 18.D. may be brought from
time to


                                      -13-


time by Landlord during the aforesaid period, on one (1) or more
occasions, without the necessity of Landlord's waiting until the expiration
of such period, and in no event shall Tenant be entitled to any excess of
rental (or rental plus other sums) obtained by reletting over and above the
rental provided for in this Lease.

          E.   In the event that Landlord elects to repossess the Leased
Premises without terminating this Lease, then Tenant shall be liable for and
shall pay to Landlord, at the address specified in Paragraph 1.C. hereof, all
rental and other indebtedness accrued to the date of such repossession, plus
rental required to be paid by Tenant to Landlord during the remainder of the
Term of this Lease until the expiration of the Term of this Lease, diminished
by any net sums thereafter received by Landlord through reletting the Leased
Premises during said period (after deducting expenses incurred by Landlord as
provided in Paragraph 18.F. hereof). In no event shall Tenant be entitled to
any excess of any rental obtained by reletting over and above the rental
herein reserved. Actions to collect amounts due by Tenant as provided in this
Paragraph 18.E. may be brought from time to time, on one (1) or more
occasions, without the necessity of Landlord's waiting until the expiration
of the Term of this Lease.

          F.   In case of an Event of Default, Tenant shall also be liable
for and shall pay to Landlord, at the address specified in Paragraph 1.C.
hereof, in addition to any sum provided to be paid above: (i) broker's fees
incurred by Landlord in connection with reletting the whole or in part of the
Leased Premises, (ii) the cost of removing and storing Tenant's or other
occupant's property, (iii) the cost of repairing, altering, remodeling or
otherwise putting the Leased Premises into condition acceptable to a new
tenant or tenants, and (iv) all reasonable expenses incurred by Landlord in
enforcing Landlord's remedies, including reasonable attorneys' fees. Past due
rental and other past due payments shall bear interest from maturity at the
highest lawful rate per annum until paid.

          G.   In the event of termination or repossession of the Leased
Premises for an Event of Default, Landlord shall not have any obligation to
relet or attempt to relet the Leased Premises, or any portion thereof, or to
collect rental after reletting; but Landlord shall have the option to relet
or attempt to relet; and in the event of reletting, Landlord may relet the
whole or any portion of the Leased Premises for any period to any tenant and
for any use and purpose.

          H.   If Tenant should fail to make any payment or cure any Event of
Default hereunder within the time herein permitted, Landlord, without being
under any obligation to do so and without thereby waiving such default, may
make such payment and/or remedy such other default for the account of Tenant
(and enter the Leased Premises for such purpose), and thereupon Tenant shall
be obligated to, and hereby agrees to, pay Landlord, upon demand, all costs,
expenses and disbursements (including reasonable attorneys' fees) incurred by
Landlord in taking such remedial action.

          I.   In the event of any default by Landlord, Tenant's exclusive
remedy shall be an action for damages and/or injunctive relief (Tenant hereby
waiving the benefit of any laws granting Tenant a lien (other than a
judgment lien) upon the property of Landlord and/or upon rental due
Landlord), but prior to any such action Tenant will give Landlord written
notice specifying such default with particularity, and Landlord shall
thereupon have thirty (30) days (plus such additional reasonable period as
may be required in the exercise by Landlord of due diligence) in which to
cure any such default. Unless and until Landlord fails to so cure any default
after such notice, Tenant shall not have any remedy or cause of action by
reason thereof. All obligations of Landlord hereunder will be construed as
covenants, not conditions; and all such obligations will be binding upon
Landlord only during the period of Landlord's possession of the Building and
not thereafter.

          The term "Landlord" shall mean only the owner, for the time being,
of the Building, and in the event of the transfer by such owner of its
interest in the Building, such owner shall thereupon be released and
discharged from all covenants and obligations of the Landlord thereafter
accruing, but such covenants and obligations shall be binding during the Term
of this Lease upon each new owner for the duration of such owner's ownership.

     19.  NONWAIVER. Neither acceptance of rental or other payments by
Landlord nor failure by Landlord to complain of any action, nonaction or
default of Tenant shall constitute a waiver of any of Landlord's rights
hereunder. Waiver by Landlord of any right for any default of Tenant shall
not constitute a waiver of any right for either a subsequent default of the
same obligation or any other default. Receipt by Landlord of Tenant's keys to
the Leased Premises shall not constitute an acceptance of surrender of the
Leased Premises.

     20.  HOLDING OVER. If Tenant should remain in possession of the Leased
Premises after the expiration of the Term of this Lease, without the
execution by Landlord and Tenant of a new lease or an extension of this
Lease, then Tenant shall be deemed to be occupying the Leased Premises as a
tenant-at-sufferance, subject to all the covenants and obligations of this
Lease and at a daily rental of 150% of the per day rental provided for the
last month of the Term of this Lease computed on the basis of a thirty (30)
day month. The inclusion of the preceding sentence shall not be construed as
Landlord's consent for Tenant to hold over. If any property not belonging to
Landlord remains at the Leased Premises after the expiration of the Term of
this Lease and Tenant's vacating the Leased Premises, Tenant hereby
authorizes Landlord to make such disposition of such property as Landlord may
desire without liability for compensation or damages to Tenant in the event
that such property is the property of Tenant; and in the event that such
property is the property of someone other than Tenant, Tenant agrees to

                                      -14-


indemnify and hold Landlord harmless from all suits, actions, liability, loss,
damages and expenses in connection with or incident to any removal, exercise or
dominion over and/or disposition of such property by Landlord.

     21.  COMMON AREA. The Common Area, as defined in Paragraph 1.P. hereof,
shall be subject to Landlord's sole management and control and shall be
operated and maintained in such manner as Landlord in Landlord's reasonable
discretion shall determine. Landlord reserves the right to change from time
to time the dimensions and location of the Common Area, to construct
additional stories on the Building and to place, construct or erect new
structures or other improvements on any part of the Land without the consent
of Tenant. Tenant, and Tenant's employees and invitees shall have the
nonexclusive right to use the Common Area as constituted from time to time,
such use to be in common with Landlord, other tenants of the Building and
other persons entitled to use the same, and subject to such reasonable rules
and regulations governing use as Landlord may from time to time prescribe.
Tenant shall not solicit business or display merchandise within the Common
Area, or distribute handbills therein, or take any action which would
interfere with the rights of other persons to use the Common Area. Landlord
may temporarily close any part of the Common Area for such periods of time as
may be necessary to prevent the public from obtaining prescriptive rights or
to make repairs or alterations.

     22.  RULES AND REGULATIONS. Tenant, and Tenant's agents, employees and
invitees shall comply fully with all requirements of the rules and
regulations of the Building which are attached hereto as EXHIBIT C and made a
part hereof. Landlord shall at all times have the right to change such rules
and regulations or to amend or supplement them in such reasonable manner as
may be deemed advisable for the safety, care and cleanliness of the Leased
Premises and the Building and for preservation of good order therein, all of
which rules and regulations, changes and amendments shall be forwarded to
Tenant and shall be carried out and observed by Tenant. Tenant shall further
be responsible for the compliance with such rules and regulations by the
employees, agents and invitees of Tenant.

     23.  TAXES. Tenant shall be liable for the timely payment of all taxes
levied or assessed against personal property, furniture or fixtures or
equipment placed by Tenant in the Leased Premises. If any such taxes for
which Tenant is liable are levied or assessed against Landlord or Landlord's
property and if Landlord elects to pay the same, or if the assessed value of
Landlord's property is increased by inclusion of personal property, furniture
or fixtures or equipment placed by Tenant in the Leased Premises, and
Landlord elects to pay the taxes based on such increase, Tenant shall pay to
Landlord upon demand that part of such taxes for which Tenant is liable
hereunder.

     24.  INSURANCE. Tenant shall, at Tenant's expense, procure and maintain
throughout the Term of this Lease a policy or policies of comprehensive
public liability insurance, contractual liability insurance and property
damage insurance, issued by insurers of recognized responsibility, authorized
to do business in the State in which the Building is located, insuring Tenant
and Landlord against any and all liability for injury to or death of a person
or persons, occasioned by or arising out of or in connection with the use or
occupancy of the Leased Premises, the limits of such policy or policies to be
in an amount of not less than $2,000,000 combined single limit with respect
to any one (1) occurrence, and shall furnish evidence satisfactory to
Landlord of the maintenance of such insurance. Tenant shall obtain a written
obligation on the part of each insurer to notify Landlord at least fifteen
(15) days prior to modification or cancellation of such insurance. In the
event Tenant shall not have delivered to Landlord a policy or certificate
evidencing such insurance at least fifteen (15) days prior to the
Commencement Date and at least fifteen (15) days prior to the expiration
dates of each expiring policy, Landlord may obtain such insurance as Landlord
may reasonably require to protect Landlord's interest. The cost for such
policies shall be paid by Tenant to Landlord as additional rental upon demand
plus an administrative charge as determined by Landlord.

     25.  PARKING. Landlord hereby leases to Tenant and Tenant hereby leases
from Landlord the number of parking spaces specified in Paragraph 1.S. hereof
in the parking facility from time to time associated with the Building at the
prevailing market rental established by Landlord from time to time for
similar parking spaces in such parking facility. Tenant shall pay to Landlord
the prevailing market rental from time to time established by Landlord for
such number of parking spaces as additional rental monthly together with and
in addition to Base Rental, whether or not such number of parking spaces are
in use. Tenant may not increase or decrease such number of parking spaces
without the prior written consent of Landlord. Tenant agrees to comply with
such reasonable rules and regulations as may be promulgated from time to time
for the use of such parking facility, including, without limitation, rules
and regulations requiring the parking of vehicles in designated spaces or
areas to the exclusion of other spaces or areas. Parking spaces will be
unassigned, provided that Landlord may at any time assign parking spaces.
Tenant shall, if requested by Landlord, furnish to Landlord a complete list
of the license plate numbers of all vehicles operated by Tenant, Tenant's
employees and agents. Landlord shall not be liable for any damage of any
nature whatsoever to, or any theft of, vehicles, or contents therein, in or
about such parking facility. During temporary periods of construction or
repair, Landlord shall use Landlord's best efforts to provide suitable
substitute parking facilities in reasonable proximity to the Building;
provided, however, if for any reason Landlord fails or is unable to provide
suitable substitute parking facilities in reasonable proximity to the
Building, Landlord shall not be deemed to be in default hereunder, but
Tenant's obligation to pay the prevailing market rental for any such parking
spaces shall cease for so long as Tenant does not have the use of such
parking spaces and such abatement shall constitute full settlement of all
claims that Tenant might otherwise have against Landlord by reason of such
failure or inability to provide such parking spaces.


                                      -15-



    26.  PERSONAL LIABILITY. The liability of Landlord to Tenant for any
default by Landlord under the terms of this Lease shall be limited to the
proceeds of sale on execution of the interest of Landlord in the Building and
in the Land, insurance proceeds, condemnation awards and rental income, and
neither Landlord, nor any party comprising Landlord, shall be personally
liable for any deficiency. This clause shall not be deemed to limit or deny
any remedies which Tenant may have in the event of default by Landlord
hereunder which do not involve the personal liability of Landlord.

     27.  NOTICE. Any notice which may or shall be given under the terms of
this Lease shall be in writing and shall be either delivered by hand
(including commercially recognized messenger and express mail service) or
sent by United States Mail, registered or certified, return receipt
requested, postage prepaid, if for Landlord, to the Building office and at
the address specified in Paragraph 1.C. hereof, or if for Tenant, to the
address specified in Paragraph 1.E. hereof, or if for Foothill, to the
address specified in Paragraph 1.E.(1), or at such other addresses as either
party may have theretofore specified by written notice delivered in
accordance herewith. Such address may be changed from time to time by either
party by giving notice as provided herein. Notice shall be deemed given when
delivered (if delivered by hand) or, whether actually received or not, five
(5) days after postmarked (it sent by mail). If the term "Tenant" as used in
this Lease refers to more than one (1) person and/or entity, and notice given
as aforesaid to any one of such persons and/or entities shall be deemed to
have been duly given to Tenant.

     28.  LANDLORD'S MORTGAGEE. If the Building and/or Leased Premises are at
any time subject to a ground lease, mortgage, deed of trust or other lien,
then in any instance in which Tenant gives notice to Landlord alleging
default by Landlord hereunder, Tenant will also simultaneously give a copy of
such notice to each Landlord's Mortgagee (provided Landlord or Landlord's
Mortgagee shall have advised Tenant of the name and address of Landlord's
Mortgagee) and each Landlord's Mortgagee shall have the right (but no
obligation) to cure or remedy such default during the period that is
permitted to Landlord hereunder, plus an additional period of thirty (30)
days, and Tenant will accept such curative or remedial action (if any) taken
by Landlord's Mortgagee with the same effect as if such action had been taken
by Landlord.

     29.  BROKERAGE. Each party represents and warrants that it has dealt
with no broker, agent or other person in connection with this transaction and
that no broker, agent or other person brought about this transaction, other
than Broker specified in Paragraph 1.R. hereof, and each party agrees to
indemnify and hold the other party harmless from and against any claims by
any other broker, agent or other person claiming a commission or other form
of compensation by virtue of having dealt with the indemnifying party with
regard to this leasing transaction. The provisions of this Paragraph 29 shall
survive the termination of this Lease.

     30.  PREPAID RENTAL AND SECURITY DEPOSIT. Landlord hereby acknowledges
receipt from Tenant of the sum stated in Paragraph 1.M. hereof to be applied
to the first accruing monthly installments of rental. Landlord further
acknowledges receipt from Tenant of a Security Deposit in the amount stated
in Paragraph 1.N. hereof to be held by Landlord as security for the
performance by Tenant of Tenant's covenants and obligations under this Lease,
it being expressly understood that such deposit shall not be considered an
advance payment of rental or a measure of Landlord's damages in case of
default by Tenant. The Security Deposit shall be held by Landlord without
liability to Tenant for interest, and Landlord may commingle such deposit
with any other funds held by Landlord. If Tenant should be late in the making
of any payment of rental or other sum due under this Lease, after any
applicable notice and cure period, three (3) or more times in a twelve (12)
month period, Tenant agrees that, upon request of Landlord, Tenant will
increase forthwith the amount of the Security Deposit to a sum double the
existing amount thereof. Upon the occurrence of any Event of Default, Landlord
may, from time to time, without prejudice to any other remedy, use such fund
to the extent necessary to make good any arrears of rental and any other
damage, injury, expense or liability caused to Landlord by such Event of
Default. Following any such application of the Security Deposit, Tenant shall
pay to Landlord on demand the amount so applied in order to restore the
Security Deposit to the amount thereof immediately prior to such application.
If Tenant is not then in default hereunder, any remaining balance of such
deposit shall be returned by Landlord to Tenant upon termination of this
Lease; provided, however, Landlord shall have the right to retain and expend
such remaining balance for cleaning and repairing the Leased Premises if
Tenant shall fail to deliver up the same at the expiration or earlier
termination of this Lease in the condition required by the provisions of this
Lease. If Landlord transfers Landlord's interest in the Leased Premises
during the Term of this Lease (including any renewal thereof), Landlord may
assign the Security Deposit to the transferee and thereafter shall have no
further liability for the return of the Security Deposit.

     31.  SPRINKLERS.

          A.   If there now is or shall be installed in the Building a
sprinkler system, and such system or any of its components shall be damaged
or injured or not in proper working order by reason of any negligence or
willful misconduct of Tenant, Tenant's agents servants, employees, or
licensees, then Tenant shall forthwith restore the same to good working
condition at Tenant's own expense; and if the Board of Fire Underwriters or
any bureau, department or official of the state or local government require
or recommend that any changes, modifications, alterations or additional
sprinkler heads or other equipment be made or supplied by reason of Tenant's
business, or the location of partitions, trade fixtures or other contents of
the Leased Premises, or for any other reason, or if any such changes,
modifications alterations, additional sprinkler heads or other equipment
become necessary to prevent the imposition of a penalty or charge against the
full allowance for a sprinkler system in the fire insurance rate as

                                      -16-


fixed by the Board of Fire Underwriters, or by any fire insurance company,
Tenant shall, at Tenant's expense, promptly make and supply such changes,
modifications, alterations, additional sprinkler heads or other equipment.

          B.   Subject to Landlord's prior written approval of the plans and
specifications, manner of installation thereof and the contractors who will
perform such work, such approvals not to be unreasonably withheld or delayed,
and subject to compliance with all applicable governmental laws, ordinances,
rules and regulations and the terms and conditions of Paragraph 36 of this
Lease, Tenant shall have the right to install a dry-pre-action fire sprinkler
system or cap off the existing sprinkler system in the Leased Premises and
install an FM200 gas system.

     32.  INTERCONNECTION RIGHTS.

          A.   Landlord acknowledges that the nature of Tenant's business may
require it to interconnect with other telecommunications companies which may
also be located in the Building. Landlord agrees that Tenant may, subject to
the payment of a Riser Fee as set forth in Paragraph 1.L. and subject to
Landlord's prior written approval, which approval, subject to the following
provisions, shall not be unreasonably withheld:

               i.    install, maintain and use cable, conduits, wires, cable
     ducts, telephone closets and ladder racks for the conduct of its business
     between the Leased Premises and other parts of the Building; and

               ii.   directly connect to, interface with, or otherwise attach
     to, the lines and facilities of the public utilities supplying electrical
     or telephone services to the Building, for additional electric energy and
     telephone connection to the Leased Premises.

          B.   In the event that Tenant desires to make any of the foregoing
modifications or improvements, Tenant shall provide written notice to
Landlord describing the type, size, location and manner of such desired
modification or improvement. Landlord shall advise Tenant in writing of
Landlord's approval or disapproval of such requested modification or
improvement, or of the requirement that Tenant submit detailed drawings and
specifications of such modification or improvement. If Landlord notifies
Tenant of the requirement that Tenant submit detailed drawings and
specifications, Tenant may then elect to withdraw its request or submit
detailed drawings and specifications, at Tenant's sole cost and expense,
regarding such modification or improvement. Tenant agrees that Landlord's
disapproval of any of the foregoing modifications and improvements shall be
reasonable if any such modifications or improvements have a material
negative impact on any Building electrical, mechanical, plumbing or other
system or the structural or aesthetic integrity of the Building or if space
is not available for such installation after taking into consideration the
needs of Landlord and of other tenants existing as of the date hereof in the
Building. Subject to Landlord's prior written approval, Tenant shall have
access to and use of all common areas, lines, chase ways and ways of passage
in the Building and the Leased Premises necessary to effectuate the rights
set forth in this paragraph, provided said access and use does not
unreasonably interfere with the operation of the Building, the existing (as
of the date of this Lease) equipment of other tenants or Landlord's
obligations to other tenants in the Building which tenants occupy space in
the Building as of the date of this Lease. Any installation carried out by
Tenant pursuant to this paragraph shall be at Tenant's sole cost and expense,
shall be performed in accordance with the other provisions of this Lease, and
shall comply with all applicable federal, state and local laws and
ordinances. Tenant agrees to indemnify and hold Landlord harmless from and
against any and all loss, cost, claim and liability (including all reasonable
attorneys' fees) for injuries to all persons and for damage to or loss of all
property arising or alleged to arise from any negligence or willful
misconduct of Tenant or Tenant's agents, employees, or contractors relating
to the installation, maintenance, operation and removal of such improvements,
installations and modifications. Notwithstanding any contrary provision
herein, Landlord shall have the right to relocate, at Landlord's expense,
any and all of the improvements described in this Paragraph 32 to another
location in the Project, as Landlord shall elect at any time and from time to
time for a reasonable purpose to Landlord's operations or utilization of the
Project; provided, however, that no such relocation may have any detrimental
effect on Tenant's use and operation of such improvements. Tenant shall cause
such improvements to be moved to the new location, at Landlord's expense,
within a reasonable time after notice from Landlord containing the details of
the new location, and the license granted in this paragraph shall be deemed
amended to the new location effective upon the receipt of the notice. Upon
ten (10) days prior notice to Tenant, Landlord shall have the right, without
liability to Tenant, to remove such improvements from the previous location
if Tenant has not relocated such improvements to the new location within the
permitted time period, which removal may involve cutting any or all cables or
otherwise interrupting service through such improvements. In the event of
such action, Tenant shall save and hold Landlord harmless from and against
any and all demands, liability, liens, claims, losses, costs and expenses
(including reasonable attorneys' fees) relating to or arising from the
removal of such improvements and any interruption of service caused thereby.

          C.   Upon the expiration or earlier termination of the Term of
this Lease, Tenant shall remove, if requested by Landlord, any and all of the
improvements described in this Paragraph 33 in a good and workmanlike manner,
and Tenant will repair any damage occasioned by such removal. If Tenant fails
to remove such improvements within thirty (30) days after the expiration or
earlier termination of the Term of this Lease, Landlord shall have the right,
but not the obligation, to elect either (i) to remove such improvements at
Tenant's cost and expense, and Landlord shall have no liability for the
return of, or damage to, such improvements, or (ii) to treat such
improvements as abandoned by Tenant.


                                      -17-


          D.   Notwithstanding anything in this Paragraph 32 to the contrary,
the rights of Tenant and the obligations of Landlord contained in this Paragraph
32 shall apply only if no uncured Event of Default exists at the time any such
right becomes exercisable or any such obligation becomes performable.

     33.  EMERGENCY GENERATOR.

          A.   Tenant shall have the right, subject to Landlord's weight
stress, load bearing and ventilation requirements and at Tenant's sole cost
and expense, to install and maintain an emergency generator and associated
skid fuel tank in one of the parking spaces referenced in Paragraph 1.S. of
this Lease, at a location selected by Landlord and Tenant. Tenant shall
maintain, at Tenant's sole cost and expense, a fence around such emergency
generator and fuel tank. Additionally, subject to Landlord's prior written
approval of plans and specifications relating thereto, which approval shall
not be unreasonably withheld, Tenant shall have the right to install such
wire, conduits, cables and other materials as necessary to connect such
emergency generator to the Leased Premises (the emergency generator, skid
fuel tank and connecting material, being collectively referred to as the
"Generator Installation"). Tenant shall be responsible for all costs and
expenses arising from and relating to the Generator Installation. The
Generator Installation shall be in compliance with all applicable federal,
state and local laws and ordinances and Tenant shall indemnify and hold
Landlord harmless from and against any and all loss, cost, claim and
liability arising from Tenant's failure to satisfy such requirement. Landlord
agrees that Tenant and representatives designated by Tenant and reasonably
approved by Landlord shall have reasonable access to the Generator
Installation in order to install, operate, maintain, inspect and remove as
required, the Generator Installation, except when reasonable safety and
security requirements of Landlord preclude such access. Landlord shall not
unreasonably interfere with or impair Tenant's use, operation, maintenance or
repair of the Generator Installation. Subject to Landlord's obligation not to
unreasonably interfere with or impair Tenant's use, operation, maintenance or
repair of the Generator Installation, Landlord reserves the right to lease
space in the Project to other tenants, as Landlord may desire, for any
purpose, including the installation and operation of a separate emergency
generator. Notwithstanding any contrary provision contained herein, Landlord
shall have the right to relocate, at Landlord's sole expense, the Generator
Installation to another location in the Project, as Landlord shall elect;
provided, however, that no such relocation may result in any additional cost
or expense to Tenant or have any detrimental effect on Tenant's use and
operation of the Generator Installation.

          B.   Subject to Tenant's compliance with all applicable
governmental laws, rules and regulations, Tenant may install sealed batteries
for backup power ("Backup Batteries") in a location approved by Landlord.

          C.   Tenant agrees to indemnify and hold Landlord harmless from and
against any and all loss, cost, claim and liability (including all reasonable
attorneys' fees) for injuries to all persons and for damage to or loss of all
property arising or alleged to arise the installation, maintenance,
operation, existence and/or removal of the Generator Installation and/or the
Backup Batteries.

          D.   Upon the expiration or earlier termination of the Term of this
Lease, Tenant shall remove, if requested by Landlord, the Generator
Installation and the Back-up Batteries and related improvements in a good and
workmanlike manner, and Tenant will repair any damage occasioned by such
removal. If Tenant fails to remove the Generator Installation and/or the
Backup Batteries within thirty (30) days after the expiration or earlier
termination of the Term of this Lease, Landlord shall have the right, but not
the obligation, to elect either (i) to remove the Generator Installation
and/or the Backup Batteries at Tenant's cost and expense, and Landlord shall
have  no liability for the return of, or damage to, the Generator
Installation and/or the Backup Batteries, or (ii) to treat the Generator
Installation and/or the Backup Batteries as abandoned by Tenant.

     34.  SUPPLEMENTAL HVAC.

          A.   Tenant shall have the right to install and maintain, at
Tenant's sole cost and expense, supplemental air-conditioning equipment in
one of the parking spaces referenced in Paragraph 1.S. of this Lease, at a
location selected by Landlord and Tenant. Tenant shall maintain, at Tenant's
sole cost and expense, a fence around such supplemental air conditioning
equipment. Additionally, subject to Landlord's prior written approval of
plans and specifications relating thereto, Tenant shall have the right to
install such air, conduits, cables and other materials as necessary to
connect such supplemental air conditioning equipment to the Leased Premises
(the supplemental air conditioning equipment and connecting material being
collectively referred to as the "HVAC Installation"). Landlord agrees not to
unreasonably withhold or delay its approval regarding matters involving the
HVAC Installation on which Landlord's approval is required. Tenant shall be
responsible for all costs and expenses arising from and relating to the HVAC
Installation. The HVAC Installation shall be in compliance with all
applicable federal, state and local laws and ordinances and Tenant shall
indemnify and hold Landlord harmless from and against any and all loss,
cost, claim and liability arising from Tenant's failure to satisfy such
requirement.

          B.   Tenant agrees to indemnify and hold Landlord harmless from and
against any and all loss, cost, claim and liability (including all
reasonable attorneys' fees) for injuries to all persons and for damage to or
loss of all property arising or alleged to arise from the installation,
maintenance, operation, existence and/or removal of the Installation.


                                      -18-



          C.   Landlord agrees that Tenant and representatives designated by
Tenant and approved by Landlord shall have reasonable access to the HVAC
Installation in order to install, operate, maintain, inspect and remove as
required, the HVAC Installation, except when reasonable safety and security
requirements of Landlord preclude such access. Landlord shall not unreasonably
interfere with or impair Tenant's use, operation, maintenance or repair of the
HVAC Installation.

          D.   Subject to Landlord's obligation not to unreasonably interfere
with or impair Tenant's use, operation, maintenance or repair of the HVAC
Installation, Landlord reserves the right to lease space in the Project to other
tenants, as Landlord may desire, for any purpose, including the installation and
operation of supplemental air conditioning equipment.

          E.   Notwithstanding any contrary provision contained herein, Landlord
shall have the right to relocate, at Landlord's sole expense, the HVAC
Installation to another location in the Project, as Landlord shall elect;
provided, however, that no such relocation may result in any additional cost or
expense to Tenant or have any detrimental effect on Tenant's use and operation
of the HVAC Installation.

          F.   Upon the expiration or earlier termination of the Term of this
Lease, Tenant shall remove, if requested by Landlord, the HVAC Installation and
related improvements in a good and workmanlike manner, and Tenant will repair
any damage occasioned by such removal. If Tenant fails to remove the HVAC
Installation within thirty (30) days after the expiration or earlier termination
of the Term of this Lease, Landlord shall have the right, but not the
obligation, to elect either (i) to remove the HVAC Installation at Tenant's cost
and expense, and Landlord shall have no liability for the return of, or damage
to, the HVAC Installation, or (ii) to treat the HVAC Installation as abandoned
by Tenant.

     35.  DELIVERY OF LEASED PREMISES.

          A.   Tenant hereby leases the Leased Premises on an "as is," "where
is" basis without representation or warranty, express or implied. Landlord shall
have no obligation to construct or install leasehold improvements in the Leased
Premises.

          B.   Tenant shall construct or have constructed in a first class and
workmanlike manner the tenant finish improvements (the "Tenant Finish Work") to
be constructed and installed in the Leased Premises. The Tenant Finish Work
shall be constructed in accordance with plans and specifications prepared or
caused to be prepared by Tenant, at Tenant's sole cost and expense, and
approved in advance, in writing, by Landlord, such approval not to be
unreasonably withheld or delayed. The Tenant Finish Work shall be constructed in
accordance with all applicable building laws and ordinances and all covenants,
conditions and restrictions affecting the Building. Tenant shall obtain
Landlord's written approval of Tenant's bid package prior to delivering the bid
package to prospective contractors, such approval not to be unreasonably
withheld or delayed.

          C.   Tenant shall not commence the construction of any portion of the
Tenant Finish Work until Landlord has approved, in writing, the contractors who
shall perform the Tenant Finish Work, such approval not to be unreasonably
withheld or delayed.

          D.   The costs and expenses of installing and constructing the Tenant
Finish Work shall be borne solely by Tenant; provided, however that Landlord
shall provide to Tenant an allowance (the "Tenant Finish Allowance") with
respect to the construction of the Tenant Finish Work in an amount equal to the
product of Three and No/100 Dollars ($3.00) multiplied by the number of rentable
square feet of area located in the Leased Premises. The Tenant Finish Allowance
shall be disbursed to Tenant within thirty (30) days following (a) the
completion of the Tenant Finish Work, as reasonably determined by a
representative of Landlord, and (b) Tenant's delivery to Landlord of the paid
bills or invoices for such work and final unconditional releases or waivers of
mechanic's and materialmen's liens from all parties who have furnished materials
or services or performed labor of any kind in connection with the Tenant Finish
Work. A construction management fee equal to five percent (5%) of the cost of
the Tenant Finish Work shall be deducted from the Tenant Finish Allowance and
paid to Landlord's designated construction manager. Tenant shall be entitled
only to that portion of the Tenant Finish Allowance which is evidenced by paid
bills or invoices for Tenant Finish Work actually performed by third parties,
and any unused portion of the Tenant Finish Allowance as of the Commencement
Date shall be the sole and exclusive property of Landlord.

     36.  REMOVAL OF ABOVE-CEILING ALTERATIONS. At the termination of this
Lease, Tenant shall, at Tenant's sole cost and expense, remove all above-ceiling
alterations made by or on behalf of Tenant to the Leased Premises, including,
without limitation, the initial alterations made to the Leased Premises, and
repair all damage caused thereby. In addition, Tenant shall, at Tenant's sole
cost and expense, replace all above-ceiling improvements removed by Tenant or on
behalf of Tenant from the Leased Premises so that Tenant shall return the
above-ceiling portion of the Leased Premises to Landlord in the same condition
as it exists on the date of this Lease. Such work shall be done in a good and
workmanlike manner and in accordance with the terms and conditions of Paragraph
11 of this Lease.


                                   -19-



     37.  RENEWAL OPTIONS. If there is no uncured Event of Default hereunder,
Tenant shall have the right to renew the Term of this Lease for two (2)
additional periods of five (5) years each upon the same terms, conditions and
provisions applicable to the primary term of this Lease (unless otherwise
expressly provided herein), except that the annual Base Rental (which shall
include a Riser Fee) for each additional term of five (5) years shall equal the
product of the number of square feet of rentable area then contained in the
Leased Premises multiplied by an amount equal to the then prevailing market base
rental rate (including market riser fee rate) per rentable square foot per annum
charged for comparable space in comparable buildings and with comparable use in
the central business district of Dallas, Texas, as reasonably determined by
Landlord (taking into account that the Base Operating Expenses Rate shall remain
unchanged and Tenant pays for certain utilities and services directly as
provided in this Lease).

     Tenant shall evidence its intent to exercise its right of renewal
separately with respect to each renewal term by delivering to Landlord written
notice ("Tenant's Renewal Notice") of Tenant's desire to renew the Term of this
Lease as aforesaid at least six (6) months (but not more than twelve (12)
months) prior to the expiration of the then current Term of this Lease. Within
thirty (30) days following delivery of Tenant's Renewal Notice, Landlord shall
deliver to Tenant a written notice ("Landlord's Notice") specifying the Base
Rental rate (including Riser Fee rate) per rentable square foot per annum for
the applicable additional term of five (5) years. Tenant shall have thirty (30)
days following delivery of Landlord's Notice in which to notify Landlord of
Tenant's exercise of its rights to renew the Term hereof. Failure to notify
Landlord within such period or to timely deliver Tenant's Renewal Notice shall
automatically extinguish Tenant's rights to renew. Tenant shall have no right to
renew the Term of this Lease following the expiration of the second renewal term
of five (5) years detailed herein.

     38.  ROOFTOP RIGHTS. Landlord and Tenant contemplate entering into a
separate agreement to be negotiated with Tenant by Landlord or Landlord's roof
consultant addressing Tenant's rights, if any, with respect to the Building's
rooftop.

     39.  MISCELLANEOUS.

          A.   Provided Tenant complies with Tenant's covenants, duties and
obligations hereunder, Tenant shall quietly have, hold and enjoy the Leased
Premises subject to the terms and provisions of this Lease without hindrance
from Landlord or any person or entity claiming by, through or under Landlord.

          B.   In any circumstance where Landlord is permitted to enter upon the
Leased Premises during the Term of this Lease, whether for the purpose of curing
any default of Tenant, repairing damage resulting from fire or other casualty or
an eminent domain taking or is otherwise permitted hereunder or by law to go
upon the Leased Premises, no such entry shall constitute an eviction or
disturbance of Tenant's use and possession of the Leased Premises or a breach by
Landlord of any of Landlord's obligations hereunder or render Landlord liable
for damages for loss of business or otherwise or entitle Tenant to be relieved
from any of Tenant's obligations hereunder or grant Tenant any right of setoff
or recoupment or other remedy; and in connection with any such entry incident to
performance of repairs, replacements, maintenance or construction, all of the
aforesaid provisions shall be applicable notwithstanding that Landlord may elect
to take building materials in, to or upon the Leased Premises that may be
required or utilized in connection with such entry by Landlord. Landlord shall
use reasonable efforts not to interfere with the operation of Tenant's business
in the Leased Premises during such entry.

          C.   [Intentionally Deleted.]

          D.   The remedies of Landlord hereunder shall be deemed cumulative,
and no remedy of Landlord, whether exercised by Landlord or not, shall be
deemed to be in exclusion of any other. Except as may be otherwise herein
expressly provided, in all circumstances under this Lease where prior consent or
permission of one (1) party ("first party") is required before the other party
("second party") is authorized to take any particular type of action, the matter
of whether to grant such consent or permission shall be within the sole and
exclusive judgment and discretion of the first party; and it shall not
constitute any nature of breach by the first party hereunder or any defense to
the performance of any covenant, duty or obligation of the second party
hereunder that the first party delayed or withheld the granting of such consent
or permission, whether or not the delay or withholding of such consent or
permission was prudent or reasonable or based on good cause.

          E.   In all instances where Landlord or Tenant is required to pay any
sum or do any act at a particular indicated time or within an indicated period,
it is understood that time is of the essence.

          F.   The obligation of Tenant to pay all rental and other sums
hereunder provided to be paid by Tenant and the obligation of Tenant to perform
Tenant's other covenants and duties hereunder constitute independent,
unconditional obligations to be performed at all times provided for hereunder,
save and except only when an abatement thereof or reduction therein is
hereinabove expressly provided for and not otherwise. Tenant waives and
relinquishes all rights which Tenant might have to claim any nature of lien
against or withhold, or deduct from or offset against any rental and other sums
provided hereunder to be paid Landlord by Tenant. Tenant waives and relinquishes
any right to assert, either as a claim or as a defense, that Landlord is bound
to perform or is liable for the nonperformance of any implied covenant or
implied duty of Landlord not expressly herein set forth.


                                   -20-



          G.   Under no circumstances whatsoever shall Landlord or Tenant ever
be liable hereunder for consequential damages or special damages.

          H.   Landlord retains the exclusive right to create any additional
improvements to structural and/or mechanical systems, interior and exterior
walls and/or glass, which Landlord deems necessary without the prior consent of
Tenant. Landlord shall use reasonable efforts not to interfere with Tenant's
operation of its business in the Leased Premises during the exercise of the
foregoing right.

          I.   All monetary obligations of Landlord and Tenant (including,
without limitation, any monetary obligation of Landlord or Tenant for damages
for any breach of the respective covenants, duties or obligations of Landlord or
Tenant hereunder) are performable exclusively in the county in which the
Building is located.

          J.   The laws of the State in which the Building is located shall
govern the interpretation, validity, performance and enforcement of this Lease.

          K.   If any clause or provision of this Lease is or becomes illegal,
invalid, or unenforceable because of present or future laws or any rule or
regulation of any governmental body or entity, effective during the Term of this
Lease, the intention of the parties hereto is that the remaining parts of this
Lease shall not be affected thereby.

          L.   [Intentionally Deleted.]

          M.   It is mutually agreed by and between Landlord and Tenant that the
respective parties hereto shall and they hereby do waive trial by jury in any
action, proceeding or counterclaim brought by either of the parties hereto
against the other on any matters whatsoever arising out of or in any way
connected with this Lease, the relationship of landlord and tenant, Tenant's use
or occupancy of the Leased Premises, and any emergency statutory or any other
statutory remedy.

          N.   [Intentionally Deleted.]

          O.   No receipt of money by Landlord from Tenant after the expiration
of the Term of this Lease, or after the service of any notice, or after the
commencement of any suit, or after final judgment for possession of the Leased
Premises, shall reinstate, continue or extend the Term of this Lease or affect
any such notice, demand or suit or imply consent for any action for which
Landlord's consent is required.

          P.   [Intentionally Deleted.]

          Q.   Words of any gender used in this Lease shall be held and
construed to include any other gender, and words in the singular number shall be
held to include the plural, unless the context otherwise requires. The headings
of the Paragraphs of this Lease have been inserted for convenience only and are
not to be considered in any way in the construction or interpretation of this
Lease.

          R.   Tenant agrees that Tenant shall from time to time upon request by
Landlord and/or Landlord's Mortgagee execute and deliver to Landlord a statement
in recordable form certifying (i) that the Lease is unmodified and in full force
and effect (or, if there have been modifications, that the same is in full force
and effect as so modified), (ii) the dates to which rental and other charges
payable under this Lease have been paid, and (iii) that Landlord is not in
default hereunder (or, if Landlord is in default, specifying the nature of such
default). Tenant further agrees that Tenant shall from time to time upon request
by Landlord execute and deliver to Landlord an instrument in recordable form
acknowledging Tenant's receipt of any notice of assignment of this Lease by
Landlord.

          S.   In no event shall Tenant have the right to create or permit there
to be established any lien or encumbrance of any nature against the Leased
Premises or the Building for any improvement or improvements by Tenant, and
Tenant shall fully pay the cost of any improvement or improvements made or
contracted for by Tenant. Any mechanic's lien filed against the Leased Premises
or the Building for work claimed to have been done, or materials claimed to have
been furnished to Tenant, shall be duly discharged (by payment or bonding) by
Tenant within ten (10) days after the filing of the lien.

          T.   Whenever a period of time is herein prescribed for action to be
taken by a party (other than the payment of rental obligations hereunder), such
party shall not be liable or responsible for, and there shall be excluded from
the computation for any such period of time, any delays due to strikes, riots,
acts of God, shortages of labor or materials, war, governmental laws,
regulations or restrictions, or any other causes of any kind whatsoever which
are beyond the reasonable control of the party obligated to take such action.

          U.   This Lease shall not be recorded by either party without the
consent of the other.

          V.   Nothing herein contained shall be deemed or construed by the
parties hereto, nor by any third party, as creating the relationship of
principal and agent, or of partnership or of joint venture between the parties
hereto, it being understood and agreed that neither the method of the
computation of rental, nor any other


                                      -21-



provision contained herein, nor any acts of the parties hereto, shall be deemed
to create any relationship between the parties hereto other than the
relationship of landlord and tenant.

          W.   Whenever it is provided herein that a monetary sum shall be due
to Landlord together with interest at the highest lawful rate, if at such time
there shall be no highest rate prescribed by applicable law, interest shall be
due at the rate of two percent (2%) in excess of Prime Rate as defined in
Paragraph 1.Q. hereof.

          X.   Tenant acknowledges that Landlord's agents and employees have
made no representations or promises with respect to the Leased Premises or the
Building except as herein expressly set forth, and Tenant further acknowledges
that no rights, easements or licenses are acquired by Tenant by implication or
otherwise, except as herein expressly set forth.

          Y.   Tenant warrants that Tenant is, and shall remain throughout the
Term of this Lease, authorized to do business in the State in which the Building
is located. Tenant agrees, upon request by Landlord, to furnish Landlord
satisfactory evidence of Tenant's authority for entering into this Lease.

          Z.   If either party brings an action to enforce the terms hereof or
declare rights hereunder, the prevailing party in any such action, on trial or
appeal, shall be entitled to his reasonable attorney's fees to be paid by the
losing party as fixed by the court.

          AA.  In the event Tenant requests from Landlord the written consent of
Landlord to any proposed assignment of the Lease or subletting of any or all of
the Leased Premises, Landlord may require the payment of reasonable attorney's
fees incurred by Landlord in processing such request, regardless of whether such
consent is granted. Such fee shall be payable by Tenant at the time such request
is made by Tenant.

          BB.  Submission of this Lease for examination does not constitute
an offer, right of first refusal, reservation of, or option for, the Leased
Premises or any other premises in the Building. This Lease shall become
effective only upon execution and delivery by both Landlord and Tenant.

          CC.  If Tenant is composed of more than one (1) person or entity, each
person and/or entity comprising Tenant shall be jointly and severally liable for
the performance of the obligations of Tenant under this Lease, including
specifically, without limitation, the payment of rental and all other sums
payable hereunder.

          DD.  Landlord shall have the right at any time to change the name or
street address of the Building and to install and maintain a sign or signs on
the interior or exterior of the Building.

          EE.  Any charges against Tenant by Landlord for services or for work
done on the Leased Premises by order of Tenant, or otherwise accruing under this
Lease, shall be considered as rental due and shall be included in any lien for
rental.

          FF.  If at any time during the Term of this Lease a tax or excise on
rental, a sales tax or other tax however described (except any inheritance,
estate, gift, income or excess profit tax imposed upon Landlord) is levied or
assessed against Landlord by any taxing authority having jurisdiction on
account of Landlord's interest in this Lease, or the rentals or other charges
payable hereunder, as a substitute in whole or in part for, or in addition to,
the taxes described elsewhere in this paragraph. Tenant shall pay to Landlord as
additional rental upon demand the amount of such tax or excise. In the event
that any such tax or excise is levied or assessed directly against Tenant,
Tenant shall pay the same at such times and in such manner as such taxing
authority shall require.

          GG.  Tenant has no right to protest the real estate tax rate assessed
against the Project and/or the appraised value of the Project determined by any
appraisal review board or other taxing entity with authority to determine tax
rates and/or appraised values (each a "Taxing Authority"). Tenant hereby
knowingly, voluntarily and intentionally waives and releases any right, whether
created by law or otherwise, to (a) file or otherwise protest before any Taxing
Authority any such rate or value determination even though Landlord may elect
not to file any such protest; (b) receive, or otherwise require Landlord to
deliver, a copy of any reappraisal notice received by Landlord from any Taxing
Authority; and (c) appeal any order of a Taxing Authority which determines any
such protest. The foregoing waiver and release covers and includes any and all
rights, remedies and recourse of Tenant, now or at any time hereafter, under
Section 41.413 and Section 42.015 of the Texas Tax Code (as currently enacted or
hereafter modified) together with any other or further laws, rules or
regulations covering the subject matter thereof. Tenant acknowledges and agrees
that the foregoing waiver and release was bargained for by Landlord and Landlord
would not have agreed to enter into this Lease in the absence of this waiver and
release. If, notwithstanding any such waiver and release, Tenant files or
otherwise appeals any such protest, then Tenant will be in default under this
Lease and, in addition to Landlord's other rights and remedies, Tenant must pay
or otherwise reimburse Landlord for all costs, charges and expenses incurred by,
or otherwise asserted against, Landlord as a result of any tax protest or appeal
by Tenant, including, appraisal costs, tax consultant charges and attorneys'
fees (collectively, the "Tax Protest Costs"), If. as a result of Tenant's tax
protest or appeal, the appraised value for the Project is increased above that
previously determined by the Taxing Authority (such increase, the "Value
Increase") for the year covered by such tax protest or appeal (such year, the
"Protest Year"), then Tenant must pay Landlord, in addition to all Tax Protest
Costs, an amount (the "Additional Taxes") equal to the sum of


                                  -22-



the following: (i) the product of the Value Increase multiplied by the tax
rate in effect for the Protest Year; plus (ii) the amount of additional taxes
payable during the five (5) year period following the Protest Year, such
amount to be calculated based upon the Value Increase multiplied by the tax
rate estimated to be in effect for each year during such five (5) year
period. Tenant must pay all Additional Taxes - even those in excess of
Tenant's proportionate share and which may relate to years beyond the term of
this Lease. The Additional Taxes will be conclusively determined by a tax
consultant selected by Landlord, without regard to whether and to what extent
Landlord may be able in years following the Protest Year to reduce or
otherwise eliminate any Value Increase. All Tax Protest Costs and Additional
Taxes must be paid by Tenant within five (5) days following written demand by
Landlord.

     40.  ENTIRE AGREEMENT AND BINDING EFFECT. This Lease and any
contemporaneous workletter, addenda or exhibits signed by the parties constitute
the entire agreement between Landlord and Tenant; no prior written or prior
contemporaneous oral promises or representations shall be binding. This Lease
shall not be amended, changed or extended except by written instrument signed by
both parties hereto. The provisions of this Lease shall be binding upon and
inure to the benefit of the heirs, personal representatives, successors and
assigns of the parties, but this provision shall in no way alter the restriction
herein in connection with assignment, subletting and other transfer by Tenant.

     EXECUTED in multiple counterparts, each of which shall have the force and
effect of an original, on the date specified in Paragraph 1.A. hereof.

                                   LANDLORD:

                                   BEVERLY HILLS CENTER LLC,
                                   a California limited liability
                                    company



                                   By: M.T. Akhavizadah
                                      ----------------------------------
                                   Name: M.T. Akhavizadah
                                        --------------------------------
                                   Title: Vice President
                                         -------------------------------

                                   TENANT:

                                   COMMUNICATION TELESYSTEMS INTERNATIONAL DBA
                                   WORLDXCHANGE COMMUNICATIONS

                                   By: /s/ Edward S. Soren
                                       ---------------------------------
                                       Edward S. Soren
                                       President



                              APPROVED BY
                              LEGAL DEPT.
                              [ILLEGIBLE]
                           -----------------
                           ATTORNEY     DATE


                                       -23-



                       LIST OF OMITTED EXHIBITS AND ATTACHMENTS

          The following Exhibits and Attachments to the Office Lease Agreement
have been omitted from this Exhibit and shall be furnished supplementally to the
Commission upon request:

          Schedule A -- Leased Premises

          Exhibit B -- Land

          Exhibit C -- Rules and Regulations

          Waiver and Consent by Real Property Owners

          Consent and Waiver by Owner, Landlord or Mortgagee of Real Estate