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                                                                  EXHIBIT: 10.55

                            THIRD AMENDMENT TO LEASE


        THIS THIRD AMENDMENT TO LEASE ("Third Amendment") is made and entered
into as of February 24, 1998, by and between SGA Development Partnership, Ltd.,
a Texas limited partnership ("Landlord") and Cisco Systems, Inc., a California
corporation ("Tenant"),


        This Third Amendment is entered into upon the basis of the following
facts, understandings and intentions.

        A. Landlord and Tenant have entered into that certain Lease dated
February 25, 1993 (the "Lease") as amended by that certain First Amendment to
Lease dated May 20, 1993 (the "First Amendment") and that certain Second
Amendment to Lease (the "Second Amendment") dated May 19, 1994 (hereinafter
collectively referred to as the "Lease"), pursuant to which Landlord leased to
Tenant certain land located in San Jose, California as more particularly
described in the Lease and on Exhibit A attached hereto and incorporated herein
by this reference ("Premises"). Any capitalized terms used but not defined in
this Third Amendment which are defined in the Lease shall have the meanings
described in the Lease.

        B. Landlord and Tenant now desire to amend the terms of the Lease as
more particularly described in herein.

        NOW, THEREFORE, in consideration of the mutual covenants contained
herein, the parties hereby agree as follows:


1. Term. Section 1.6 of the Lease shall be amended to provide that (a) the Term
is extended until February 24, 2003, and (b) Tenant shall have no rights to
extend the Term of the Lease beyond February 24, 2003. For all purposes of the
Lease, the period from the date of this Third Amendment until February 24, 2003,
shall be the "Extension Term."

        2. Addresses for Notices. Section 1.9 is hereby amended by changing the
addresses for notice to Tenant to the following:

        Tenant:                 Cisco Systems, Inc.
                                170 West Tasman Drive
                                San Jose, CA 95134-1706
                                Attn:  Vice President Worldwide Real
                                Estate and Workplace Resources

        copy to:                Cisco Systems, Inc.
                                170 West Tasman Drive
                                San Jose, CA 95134-1706
                                Attn: Treasurer

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        copy to:                Brobeck, Phleger & Harrison
                                550 West C Street, Suite 1200
                                San Diego, CA  92101
                                Attn:  Ellen E. Jamason, Esq.

                and to change the address for copies of notices to Landlord to
        the following:

                                Lorne O. Liechty, Esq.
                                Liechty & McGinnis, P.C.
                                10440 North Central Expressway, Suite 1100
                                Dallas, Texas 75231

        3. Second Amendment to Promissory Note. Tenant hereby consents to the
Second Amendment to Promissory Note to be executed by Landlord and HKS effective
concurrently herewith. As used in the Lease, the term "HKS Note" shall mean the
HKS Note as the same has been previously amended and as amended by the Second
Amendment to Promissory Note.

        4. Liability Insurance. Section 7.1 of the Lease is hereby amended by
deleting Section 7.1 and substituting the following therefore:

        7.1 Public Liability Insurance. During the Term, the Tenant shall
        procure and carry, at the Tenant's sole cost and expense, commercial
        general liability insurance for claims for injuries or death sustained
        by persons or damage to property while on the Properties and such other
        public liability coverages as are ordinarily procured by the Tenant or
        its Affiliates who own or operate similar properties, but in any case
        shall provide liability coverage of at least $2,000,000 per person and
        $1,000,000 for property damage per occurrence. Such insurance shall be
        on terms and in amounts that are no less favorable than insurance
        maintained by the Tenant or such Affiliates with respect to similar
        properties that they own and that are in accordance with normal industry
        practice. The policy shall be endorsed to include the Landlord as an
        additional insured. The policy shall also specifically provide that the
        policy shall be considered primary insurance which shall apply to any
        loss or claim before any contribution by any insurance which the
        Landlord may have in force.

        5. Self-Insurance. Article 7 is further amended by adding the following
new Section 7.4:

        "The Tenant shall have the right to self-insure with respect to any of
        the insurance required under this Lease so long as (i) the Tenant is a
        publicly traded domestic corporation whose stock is traded on a
        nationally recognized exchange; (ii) the Tenant has not assigned

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        this Lease; (iii) the Tenant maintains a Consolidated Tangible Net Worth
        of at least $1,000,000,000 according to its most recent audited
        financial statement; and (iv) the Tenant governs and manages its
        self-insurance program in a manner consistent with programs managed by
        prudent businesses whose stock is publicly traded on nationally
        recognized exchanges. Upon request, the Tenant shall supply the Landlord
        from time to time with evidence reasonably satisfactory to the Landlord
        of the Tenant's net worth and the satisfaction of the condition set
        forth above. If the Tenant elects to self-insure, the Tenant shall be
        responsible for losses or liabilities which would have been assumed by
        the insurance companies which would have issued the insurance required
        of the Tenant under the Lease. The Tenant will notify the Landlord in
        advance of any period for which it intends to self-insure and shall
        provide Landlord with satisfactory evidence that it complies with these
        requirements in order to give the Tenant an opportunity to confirm the
        satisfaction of the conditions set forth above. For so long as the
        Tenant self-insures, the Tenant, for applicable periods, shall and does
        hereby indemnify and hold harmless the Landlord, its officers,
        directors, agents, employees and representatives from and against all
        costs, damages or expenses (including reasonable attorneys' fees)
        incurred or paid by the Tenant as a result of any claim customarily
        covered by a broad-form policy of commercial general liability
        insurance, including a contractual liability endorsement.

        6. Tenant Deed of Trust. Concurrently with the effective date of this
Third Amendment, Landlord shall execute, acknowledge and cause to be recorded in
the Official Records of Santa Clara County, California a Deed of Trust in form
acceptable to Tenant ("Tenant Deed of Trust"), which Tenant Deed of Trust shall
secure Landlord's obligations under this Lease to convey the Premises to Tenant
as required pursuant to Article 19 of the Lease. The Tenant Deed of Trust shall
be junior only to the Sumitomo/HKS Deed of Trust and subject to the Permitted
Exceptions.

        7. Landlord's Default. Section 17.8 shall be amended by adding the
following sentence:

        "In addition, in the event of a default by Landlord under Section 20.7,
        Tenant shall have the right to cure such default on behalf of and at
        Tenant's expense (unless such default is due to Landlord's gross
        negligence or willful misconduct, in which case such cure shall be at
        Landlord's expense), without prior notice to Landlord.

        8. Additional Covenants of Landlord. The following Section 20.7 shall be
added as follows:

        "20.7 Default Under Authorized Loan. Landlord shall not,

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        without Tenant's express prior written consent, default under any
        Authorized Loan, or any loan document relating to such Authorized Loan,
        where such default is not caused, directly or indirectly by a breach of
        any of Tenant's obligations under this Lease, under the Pledge Agreement
        securing the HKS Note or under any other documents relating to any
        Authorized Loan.

        9. Continuing Obligations. Except as modified by this Third Amendment,
the terms of the Lease remain in full force and effect. To the extent of any
conflict between the terms of the Lease and the terms of this Third Amendment,
the terms of this Third Amendment shall control.

        10. Authority. Each party represents to the other that the execution,
delivery and performance of this Third Amendment has been duly authorized by all
necessary corporate or partnership action and has been duly executed and
delivered. Each individual executing this Third Amendment on behalf of a party
represents that he or she has been duly authorized to so execute this Third
Amendment for such party.

        11. Counterparts. This Third Amendment may be executed in any number of
counterparts, each of which shall be deemed to be an original and all of which
taken together shall comprise but a single instrument.

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        IN WITNESS WHEREOF, Landlord and Tenant have executed this Third
Amendment as of the date and year first above written.

                                "LANDLORD"

                                SGA DEVELOPMENT PARTNERSHIP, LTD.,
                                a Texas limited partnership

                                By: Papita, Inc.,
                                    a Texas limited partnership
                                    Its: General Partner

                                By:
                                   ---------------------------------

                                By: Wolverine Holding Company,
                                    a Texas corporation
                                    Its:  General Partner

                                By:
                                   ---------------------------------
                                
                                By:
                                   ---------------------------------


                                "TENANT"

                                CISCO SYSTEMS, INC., a California corporation


                                By:
                                   ---------------------------------

                                By:
                                   ---------------------------------