Exhibit 10.20

AMENDMENT NO. 2 TO LEASE

1. Parties.
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This Amendment, dated June 7, 1995, is between Andover Mills Realty Limited
Partnership ("Landlord") and FTP Software, Inc. ("Tenant").

2. Recitals.
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2.1 Landlord and Tenant have entered into a Lease, dated October 1, 1993,
as amended, for space at Brickstone Square in Andover, Massachusetts (the
"Lease"). Unless otherwise defined, terms used in this Amendment have the same
meanings as those used in the Lease.

2.2 Tenant wants to lease the following additional space in the Project
(the "Additional Space"): a portion of the first (1st) floor of the Building
which is depicted in Exhibit "AA" attached hereto and incorporated herein by
this reference, and is initially agreed to contain 40,314 square feet of
rentable area. Tenant also wants an option to lease other space in the
Building. To accomplish these and other matters, for Ten and No/100 Dollars
($10.00) and other good and valuable consideration, the receipt and sufficiency
of which is acknowledged, the parties agree and the Lease is amended as follows,
notwithstanding anything to the contrary:

3. Amendments.
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3.1 "Additional Space Start Date" means the earlier of: the date that
Tenant occupies the Additional Space for the conduct of its business, or the
date that Landlord substantially completes Landlord's Work for the Additional
Space as described in this Amendment. Substantial completion will be determined
in the same manner as in Section 2 of the Lease.

3.2 As of the Additional Space Start Date the Premises will be deemed to
include the Additional Space, and therefore the agreed rentable area of the
Premises will be increased from 66,286 s.f. to 104,600 s.f.; and in Section
1.1(f), Tenant's Percentage will be increased form 7.05% to 11.12%.

3.3 Notwithstanding anything to the contrary, base rent for the Additional
Space will commence October 1, 1995, and during the initial term of the Lease
the annual base rent per square foot of rentable area in the Additional Space
will be as follows:

Annual Base Rent Per Rentable
-----------------------------
Lease Year Square Foot of Additional Space
- ---------- -------------------------------

10/1/95 - 3/31/96 $12.81
4/1/96 - 6/30/96 14.19
7/1/96 - 3/31/97 10.99
4/1/97 - 3/31/98 10.99
4/1/98 - 3/31/99 10.99
4/1/99 - 3/31/2000 11.45
4/1/2000 - 3/31/2001 11.45
4/1/2001 - 8/31/2002 11.45

Base rent for the Additional Space during the term of the extension Option will
be at the rates set forth in Rider #2 to the Lease.

3.4 "Landlord's Work" to prepare the Additional Space for Tenant's
initial occupancy is described in Exhibit "BB" attached hereto and incorporated
herein by this reference. Landlord will complete Landlord's Work for the
Additional Space in accordance with the terms of the Lease. All work to or for
the benefit of the Additional Space other than Landlord's Work is deemed to be
Tenant's Work, and will be completed by Tenant at its sole cost and expense and
in accordance with the terms of the Lease. Section 1.1 of Exhibit "C" to the
Lease also will be applicable to Landlord's Work and Tenant's Work with respect
to the Additional Space.

3.5 Article 26 of the Lease (Tenant's Right to Terminate) is deleted.

3.6 Article 28 of the Lease (Expansion Option), is amended as follows:

(a) The "Expansion Space" now means only the space designated
"Expansion Space" in Exhibit "AA" hereto, and no other space, and the rentable
area of the Expansion Space is agreed to be 23,212 square feet.

(b) The date by which the Expansion Option must be exercised is
changed to November 1, 1995.

(d) Section 28.3(c) and Exhibit "B" to the Lease are deleted.

3.7 Section 15.2 of the Lease is amended as follows:

As of the Additional Space Start Date, Tenant's permitted parking
will be

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increased to 301 passenger cars (Tenant's current areas are shown in Exhibit "A"
attached hereto). However, if Tenant does not validly exercise the Expansion
Option (or if it lapses or becomes null or void pursuant to the terms of the
Lease) then Tenant's permitted parking will be reduced by 15 spaces. If
Landlord ever constructs additional parking adjacent to the Building, when such
additional parking is completed Tenant will receive: for the Additional Space,
an additional 13 spaces, or the total number of such additional parking spaces
created, whichever is less; and if the Expansion Option is validly exercised and
does not lapse or become null or void, an additional 7 spaces for the Expansion
Space, or the total number of such additional parking spaces created that are
not already leased to Tenant, whichever is less.

3.8 Exhibit "A" to the Lease is deleted and Exhibit "A" attached hereto
is substituted in its place.

4. No Other Changes.
----------------

Except as set forth above, the Lease remains unchanged and in full force and
effect and there are no defaults by Landlord or Tenant thereunder.

IN WITNESS WHEREOF, intending to be legally bound, the parties have executed
this Amendment under seal as of the date first set forth above.

FTP SOFTWARE, INC.
WITNESS:
/s/ Deborah E. Sheehan By: /s/ Robert W. Goodnow, Jr.
- ------------------------------ ------------------------------
Name Printed: Name: Robert W. Goodnow, Jr.
Title: Vice President Finance
Authorized Signatory
WITNESS:

__________________________ By:
Name Printed: -------------------------------
Name:
Title:
Authorized Signatory

ANDOVER MILLS REALTY LIMITED
PARTNERSHIP

By: Niuna-Andover, Inc., general
partner
WITNESS:
/s/ John C. Cissel By: /s/ Martin Spaggat
- -------------------------- ------------------------------
Name Printed: Name:
Title: Vice President
Authorized Signatory

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EXHIBIT "AA"
------------
"THE PROJECT"
BUILDING 100
FIRST FLOOR

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EXHIBIT "A"
PARKING AREAS

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EXHIBIT "BB"
WORKLETTER
100 BRICKSTONE SQUARE
---------------------
ANDOVER, MASSACHUSETTS
----------------------
LANDLORD/TENANT SPLIT OF WORKLETTER RESPONSIBILITIES FOR
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FTP SOFTWARE, INC.
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"ADDITIONAL SPACE"
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FIRST FLOOR - WEST HALF
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February 15, 1995
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BURT HILL PROJECT 93677.00

B.1.0 GENERAL
- --------------

The Workletter is intended to show the division between Landlord's Work
(the Base Building described below) and Tenant work. Tenant's Work
includes any work not described under the Base Building heading below, and
any changes, additions or deletions to Landlord's Work requested by Tenant.
All descriptions of the split between the Landlord's versus the Tenant's
responsibilities with regard to HVAC, electrical, fire suppression, life
safety and plumbing are for the purpose of allocating cost and installation
responsibilities. The Landlord will specify, purchase, install and balance
all installations listed under the Base Building Heading. In order to
insure a coordinated system, the remaining systems that are to be specified
and installed by the Tenant must be approved by the Landlord, as must any
modifications or additions to the Base Building systems. Tenant is solely
responsible for paying and performing Tenant's Work. However, Landlord
reserves the right to install Tenant's Work (at Tenant's cost) if it
connects to or affects Landlord's Work or any code-related or life-safety-
related work.

Tenant may request that Landlord contract for all or a part of a Tenant's
Work. If Landlord agrees, this work will be deemed to be part of Tenant's
Work and not part of Landlord's Work, and will be done at Tenant's sole
cost, risk and liability and Landlord will have no cost, risk or liability.
Landlord will not be required to advance any funds for this work and at
Landlord's request Tenant will advance, or pay to Landlord within seven
days after receipt of bills, all costs (whether "hard" or "soft" costs)
incurred or which may be due in connection with this work, including
without limitation, costs for permits, design, drawing, architectural,
engineering and drafting services, contractors overhead and profit, labor,
materials and ten percent (10%) of hard and soft costs to Landlord for
Landlord's supervision, coordination and involvement. Tenant will indemnify
and hold Landlord harmless from all damages, claims and liabilities in
connection with this work.

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BASE BUILDING TENANT
- ------------- ------

B.2.0. SITE IMPROVEMENTS
- ------------------------

1. Landlord will identify
assigned parking spaces.

Landlord will prominently
display Tenant's name on an
existing brick and stone
building directory
monument.

B.3.0 STRUCTURE
- ----------------

1. Landlord is responsible for
any modifications to the
Base Building structural
system due to Base Building
construction and
improvements.

B.4.0 DEMOLITION
- -----------------

1. Landlord will prepare the
Tenant's space for the
Landlord's work and for
Tenant fit-up as designed.

B.5.0 BUILDING EXTERIOR
- ------------------------

1. No work required except for
Base Building items such as
demolition, mechanical
exhausts, fresh air intakes,
mechanical and electrical
penetrations.

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BASE BUILDING TENANT
- ------------- ------

B.6.0. HVAC (Central)
- -----------

1. All existing central 1. All special Tenant HVAC
equipment serving the equipment required for non.
Tenant but not within the typical Tenant cooling loads
Tenant's usable area, except as defined under Base
including existing: Building.

- Boiler and associated 2. All special ventilation and
circulating pumps in exhaust requirement related
ground floor mechanical to Tenant occupancy uses
room. such as mentioned in the
previous paragraph except as
- Controls associated with defined under Base Building.
the operation of the central
heating equipment. 3. Any special Tenant related
systems or equipment such
as special controls, climate
control (humidifcation), etc.

4. All modifications to the
system including ducted
returns or other upgrades to
the system to eliminate the
need for related
data/communication cable
above the ceiling.

B.7.0. HVAC (Tenant)
-----------

1. HVAC system in the Tenant area,
as further defined by the attached
Schedule of Tenant Workletter
Quantities, including:

- Distribution ductwork and
diffusers, all installed in
Landlord-provided acoustical
ceiling system.

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- HVAC controls in the Tenant
area as necessary for the
Landlord-provided system.

- Plenum ceiling and/or open
area return air provisions.

- Exhaust fans and ductwork for
toilet rooms.

- New fresh air system.

- New smoke exhaust fans.

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TENANT
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BASE BUILDING
- -------------

B.7.0. HVAC (Tenant) (continued)
- ------------

2. Landlord to provide HVAC equipment for
Tenant's computer/telephone room.
Equipment to be a Liebert Challenger unit
(size 5 to 7 1/2 tons) with rooftop
condensing unit.

3. First floor HVAC system to be connected
to the building automation control system.
Building automation system will also
monitor temperatures in various areas of
the Tenant's space. Approximately 3
sensors in each air handling unit zone may
be installed.

4. Landlord to provide baseboard heating
system at the perimeter of the Tenant's
space with zoned controls as required by
design. Acoustical sealing of partitions at
baseboard heat to be same as fifth floor.

5. Landlord to provide transfer air grills with
acoustical baffles at all locations where
partitions are constructed to underside of
structure. Areas to include Conference
Rooms and offices of Vice President and
Directors, Video Conference Center and
Exercise Area.

6. Landlord to provide new baseboard heat
covers and end caps where damaged on
existing heat.

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TENANT
------

BASE BUILDING
- -------------

HVAC NOTES
- ----------

1. HVAC systems will be designed to meet the following criteria:

- Cooling and ventilation capacity sufficient to meet accepted design
standards for the following:

a. A density of one occupant per 150 gross usable square feet.*

b. Total Tenant electrical loads of 6 watts per square foot for
lighting and convenience power.

c. One thermostat control per 2500 s.f. of Tenant usable floor area.
Additional control zones will be the Tenant's responsibility.

- Comfort Conditions:

a. Summer - maintain indoor conditions 76F, 56% rh at 90 F db/75
outdoors.

b. Winter - maintain indoor temperature of 72 F at 10 F outdoors.

2. Landlord is to provide the basic HVAC distribution and control system as
required by the Tenant Space Plan designed by H.F. Lenz Company and approved
by Tenant. Final definition of the scope of this work will be determined
once the Tenant has approved the space plan.

3. FTP Software first floor HVAC system to be connected to the Viking
temperature control system.

*To be confirmed during the preliminary design.

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TENANT
------

BASE BUILDING
- -------------

B.8.0 ELECTRICAL
- ----------------

1. All central electrical equipment and 1. All electrical provisions required to fit-up
distribution including the following: the Tenant area other than that provided by
the Landlord, as defined herein.
- 2,500 KVA pad-mounted exterior
transformer. 2. Tenant is also responsible to make
arrangements with the Massachusetts
- 480/277V service entrance. Electrical Company for an electric service
contract with the assistance of H.F. Lenz
- 4,000A main switchgear. Company.

- 480V four wire electrical riser in 3. Tenant will provide data and telephone
conduit. wiring and connections for Tenant's
systems.
- 400 amp breaker panel and a
120/208V step down K-rated
transformer for Tenant power, to be
located in an electrical closet within
the Tenant's demised premises.

- Provisions for a Tenant electrical
meter (to be installed in the electrical
meter room by Massachusetts Electric
Company at the request of the Tenant.

- Emergency power as necessary for
emergency lighting systems required
by code such as, stair and exit way
lighting and emergency lighting within
the Tenant space.

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TENANT
------

BASE BUILDING
- -------------

B.8.0 ELECTRICAL (continued)
- ----------------

- Lighting and power as required for all
central equipment rooms, elevators,
main lobby, exterior lighting, typical
floor elevator lobbies, exit ways, stair
towers, etc. These common areas
will be metered and controlled from
the house meters and control panels
respectively.

2. - Landlord will provide all raceways for
data and telephone systems including
conduit and pull wires within
partitions and all junction boxes.

3. - Landlord will provide all special and
dedicated power circuits and special
lighting and dimmers as designed by
H.F. Lenz Company.

4. - Landlord will assist the Tenant with
ordering the required electrical meter
and service contract.

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BASE BUILDING TENANT
- ------------- ------

B.9.0 FLOORING
- --------------

1. Landlord will provide direct glue-down 1. All special flooring in Tenant areas in
carpet (or sheet vinyl or VCT of excess of the carpet allowance amount, not
comparable value) with integral pad over including carpet tiles.
repaired/existing floors in those areas
requiring carpeting of floor covering within
the Tenant's demised premises. Carpet to
be Bigelow/Karastan Pamlico with Newport
News or equivalent borders and accents.

2. At the storage area, the Landlord will
provide V.C.T. and base only.

3. Landlord will furnish and install vinyl or
rubber base or bound edge carpet base for
all partitions and columns as selected by
Tenant.

4. Landlord will provide smooth, sound floors
ready to receive specified floor coverings
exclusive of the allowance.

5. In addition, Landlord will provide accent
carpet and borders as designed in common,
executive, entry areas, main corridors.

6. In addition, Landlord will provide low-
static carpet tiles (Milliken
Colorbond/Colorvision) in the
computer/telephone room or VCT.

7. Computer/telephone room will have a 6"
maximum raised access floor.

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BASE BUILDING TENANT
- ------------- ------

B.10.0 CEILINGS
- ---------------

1. Landlord will provide building standard
ceilings for the areas requiring ceilings
within the Tenant's demised space in a
regular grid "open-plan" configuration.
Tenant is to layout his partitions
accordingly. Ceilings to be at
approximately 10' + /- throughout space
accept for soffited areas required to
accommodate ductwork, utilities, and areas
designed with soffits and fascias.

2. Landlord will provide 15/16" standard face
suspension system with tegular edge tiles
throughout the Tenant space except in the
storage areas. Building standard tiles to be
Armstrong Second Look.

3. Landlord will leave all areas above the
ceiling open to the underside of the
structure above, except where full height
partitions are shown.

4. Landlord will construct bulkheads as
required to conceal distribution ductwork.

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BASE BUILDING TENANT
- ------------- ------

B.11.0 WALLS AND PARTITIONS
- ---------------------------

1. Core walls on Tenant floors will be taped,
spackled, and prime and finish painted.
Tenant demising walls and interior surface
of exterior walls will be taped, spackled,
and prime painted with one finish coat.

2. Landlord will install all non-moveable
ceiling height partitions within the Tenant's
space as required by the Tenant Space Plan,
but not in excess of the limitations of the
attached Schedule of Tenant Workletter
requirements.

3. In open plan area, Landlord will construct
half-height (60" high = maximum) walls to
receive Tenant movable furniture system
partitions. Distribution of power and
telephone/data to workstations will be
through these partitions. However, Tenant
cannot design half-height partitions in lieu
of moveable furniture system.

4. Landlord will tape, spackle, prime and
provide one finish coat on all partitions
installed as part of the Landlord's Base
Building obligations.

5. Landlord will provide tape, spackle, prime,
and Polomyx 6000 Series where designed
not to exceed the amount specified in the
Workletter quantities.

6. In addition, the Landlord will build all
walls for video conference center, exercise,
conference rooms, and executive areas
including special acoustical treatment as
designed.

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7. Landlord will build the standard tenant
partition with 5/8" drywall each side of
steel studs with acoustical insulation.
Video conference rooms, conference
rooms, and Vice President and directors'
offices and exercise rooms to be
constructed with 2 layers 5/8" drywall each
side of steel studs with acoustical
insulation, built to underside of structure.

8. Landlord to provide column capital detail
similar to FTP Software, Level 5,
Brickstone Square, including painted
drywall, soffit, fascia, and returns and
acoustic ceiling tile.

B.12.0 DOORS
- ------------

1. Landlord to furnish and install all main 1. Tenant to furnish and install all interior
building entries and exit doors and building door frames and hardware within the
perimeter, all core areas doors, and doors demised Tenant area other than those
to mechanical areas. provided by the Landlord as mentioned in
the Base Building provisions. Tenant
doors, frames, and hardware to be the same
specification as those provided by
Landlord unless otherwise the approved by the
Landlord.

2. Landlord to furnish and install 3' - 0" x 7' -
0" high white oak veneer solid core wood
doors (with hardware 26D finish) within the
Tenant's demised premises, as required by
the Tenant Space Plan, subject to submittal
and approval of Tenant's space plan by the
Landlord, and subject to the limitations of
the attached Schedule of Tenant Workletter
Quantities.

3. Landlord to furnish and install acoustical
seals and door bottoms at doors selected by
Tenant.

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BASE BUILDING TENANT
- ------------- ------

B.13.0 SPECIALTIES
- --------------------------------------

1. Landlord to furnish and install core area 1. Tenant is responsible for Tenant specific
signage for all floors. identification signs, directories, etc.

B.14.0 SPECIAL LANDLORD CONSTRUCTION
- --------------------------------------

1. Landlord will provide a transparent finished 1. With the exception of training and
hardwood framed 2-leaf suite entrance door conference rooms, Tenant to provide and
with glass sidelights on both sides. install special lighting fixtures or fixture
quantities in excess of Workletter quantity
allowance.

2. Landlord will provide glass sidelights at the 2. Tenant to provide and install all laboratory
rate of one per office with vertical blinds. equipment, fixtures, worksurfaces, etc.

3. Landlord will provide built-in casework for 3. Tenant to provide and install Tenant
a reception counter, lunch room appliances, specific security system.
and two kitchenettes.

4. Landlord will provide a directory that will
list Tenant's located within Building 100.

5. Landlord to provide three-hour rated
gypsum drywall enclosed record storage
area. Record storage to be further
protected by building standard sprinkler
system. Floor finishes to be V.C.T. within
this area. Ceiling to be exposed painted
concrete floor slab. Light fixtures to be
hung from structural slab.

6. Landlord will provide millwork, chair rails,
accent trim in common areas, conference
and video conference, exercise rooms as
designed and detailed.

7. All electrical and mechanical quantities and
locations to be as designed by H.F. Lenz
Co., Inc. and approved by FTP Software,
Inc.

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BASE BUILDING TENANT
- ------------- ------

B.14.0 SPECIAL LANDLORD CONSTRUCTION
(continued)

8. Landlord will provide a cable tray system
as designed and detailed at locations shown
on the drawings. Cable tray system to be
suspended from overhead structure and be
mounted below ceilings.

9. Landlord will provide code complying core 1. Tenant will provide exercise
toilet rooms for each sex within and for the equipment.
exclusive use of FTP Software employees.

10. Landlord will provide toilets and shower
facilities in the exercise area.

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PART C - SCHEDULE OF TENANT WORKLETTER QUANTITIES
- -------------------------------------------------

HVAC Thermostats (with protective covers) 1/2,500 Usable S.F.
HVAC Diffusers (flush with ceiling) 1/300 Usable S.F.
Lighting Fixtures 1/100 Usable S.F.
Tenant may substitute recessed incandescent light
fixtures for building standard light fixtures at
locations of Tenant's choice
Lighting Switches 1/Room, plus 1/2,000 Usable S.F. of Open Area
Convenience Outlets As designed
Sprinkler Heads As required by code
Smoke Detectors As required by code
Fire Alarm Speakers/Annunciators As required by code
Carpet and/or VCT Full Coverage
Ceilings and/or painted exposed structure Full Coverage
Interior Drywall Partitions 3,055 L.F. for "Additional Space"
2,686 L.F. for "Expansion Space"
94 Single Leaf Doors for "Additional Space"
83 Single Leaf Doors for "Expansion Space"
Includes 2 leaf suite entry doors
w/sidelights, 3 pr. butts, mortise lockset,
dummy pulls, flush bolts, closer.

Includes single leaf doors w/1 1/2 pr. butts,
passage set and door stop. Tenant may
substitute up to 25% of the single leaf door
allowance w/locksets
Polymix (6000 Series) 12,485 S.F. for "Additional Space"
10,980 S.F. for "Expansion Space"
Dedicated Outlets As designed
Transom Glass (above door height, drywall 133 L.F. for "Additional Space"
framed, butt joint glass) 177 L.F. for "Expansion Space"

Note: Portions of the quantities not used for the "Additional Space" may be
allocated to the "Expansion Space", should the Tenant exercise their
option for the "Expansion Space."

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