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                                                                    EXHIBIT 10.2

                       ARTICLE I - BASIC LEASE PROVISIONS


        Each reference in this Lease to titles or terms contained in Article I
shall be deemed to incorporate the applicable definitions or data. The Exhibits
attached to this Lease are incorporated by reference.

Date of Lease:                  December 28, 1998

Commencement Date:              March 1, 1999, Anticipated per Article III

Rent Commencement Date:         March 1, 1999

Landlord:                       NAM Partners, L.P.

Landlord's Mailing              NAM Partners, L.P.
Address:                        c/o Yale Properties USA
                                6256 Greenwich Drive
                                Suite 230
                                San Diego, CA 92122

Tenant:                         Brooktrout Technology, Inc.,
                                a Massachusetts corporation

Tenant's Mailing                Brooktrout Technology, Inc.
Address:                        Attn:  Stephen A. Ide
                                152 Second Avenue
                                Needham, MA  02194

Premises:                       Approximately Thirty Six Thousand One Hundred
                                Seventy Nine (36,179) square feet shown on
                                Exhibit in portions of the Buildings (the
                                "Building") located in that certain
                                Office/Industrial Park entitled "North Andover
                                Mills" (the "Park"), and situated on the
                                property (the "Property") legally described in
                                the description attached hereto as Exhibit B.

Term:                           Five (5) Years, beginning on the Commencement
                                Date.

Permitted Use:                  All or any part of the Premises may be used for
                                the following permitted uses: Office, research
                                and development, light assembly, and light
                                "high-tech" manufacturing provided same (a) does
                                not cause noise, odors, vibrations, waste, or
                                other emanations, and (b) are in character with
                                and harmonious with office use; and further
                                provided all of the foregoing are permitted by
                                applicable laws, rules and regulations, and for
                                no other use or purpose.

Base Rent:                      Minimum Base Monthly Rental shall be as follows:

                                Year 1      3/l/99-2/28/00      $21,666.67
                                Year 2      3/l/00-2/28/01      $37,384.97
                                Year 3      3/l/01-2/28/02      $39,254.22


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                                Year 4      3/l/02-2/28/03      $41,216.93
                                Year 5      3/l/03-2/28/04      $43,277.77

Lease Year:                     Twelve (12) month period beginning on the
                                Commencement Date (plus any partial month) and
                                each anniversary thereof.

Additional Rent:                All sums, other than Base Rent, due from Tenant
                                pursuant to the terms of this Lease.

Pro Rata Share:                 Tenant's Pro Rata Share shall be determined from
                                time to time during the Term by Landlord and
                                shall be based upon the ratio between the
                                rentable square footage of the Premises and the
                                rentable square footage of the space in all of
                                the buildings located on the Property which
                                utilize the specific utility or service provided
                                by Landlord.

Base Year:                      1999

Security Deposit:               N/A

Rent Payable Upon Execution:    $21,666.67 for the period March 1, 1999 through
                                March 31, 1999.

Broker:                         Fallon, Hines & O'Connor


                              ARTICLE II - PREMISES

        2.1   PREMISES. On the terms set forth herein, Landlord leases to
Tenant, and Tenant accepts from Landlord, the Premises.

        2.2   COMMON AREAS. The term "Common Areas" shall mean all areas within
the Property which are available for the common use of tenants of the Property
from time to time, as designated by Landlord, including but not limited to,
parking areas, driveways, sidewalks, loading areas, access roads, landscaping
and planted areas, as well as lobbies, corridors, elevators, and stairways which
provide access to the Premises. In addition, if the Premises include less than
the entire rentable floor area of any floor, the term "Common Areas" shall
include the common toilets, corridors and elevator lobby of such floor. Landlord
may, from time to time, change the size, location, nature and use of any of the
Common Areas, in any manner whatsoever. Tenant acknowledges that such activities
may result in an inconvenience or interruption to Tenant, but Tenant shall not
be entitled to any reduction in rent, or damages resulting from such
interference or interruption, unless such change(s) substantially impair
tenant's ability to continue its use of the Premises as set forth in this Lease.
Landlord shall use reasonable efforts to minimize any inconvenience or
interruption to Tenant In the event such activity by Landlord results in
interruption of Tenants use of the Premises for a period which exceed
twenty-four (24) hours, and such interruption has a material adverse effect on
Tenant's ability to continue its permitted use of the Premises, the Base Rent
shall, be reduced proportionately based on the area of the Premises effected and
therefore not used by Tenant until the earlier of when the interruption of use
is corrected or when Tenant begins using the area.




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        Tenant shall have the non-exclusive right to use the Common Areas
(excepting the parking areas which are addressed in Section 2.4 below) for the
intended purposes, subject to reasonable rules and regulations established by
Landlord from time to time. Tenant shall abide by such rules and regulations;
shall, to the extent Tenant becomes or is made aware of any violation by an
invitee of Tenant, advise such invitee of such violation, and request that such
invitee conform to Landlord's rules and regulations, and shall not interfere
with the rights of Landlord, other tenants or any other person entitled to use
the Common Areas. At any time, Landlord may close, relocate, or reconstitute any
Common Area, improve the Property or to protect Landlord's rights with respect
to the Property, as long as said activity does not have a material adverse
effect on Tenants ability to continue its permitted use of the Premises.
Landlord shall maintain or arrange to repair and maintain the Common Areas and
machinery and equipment serving Common Areas, in good condition, subject to
reasonable wear and tear.

        2.3   LANDLORD'S RESERVATIONS. Landlord reserves the right, from time to
time, provided Landlord uses reasonable efforts to limit unreasonable
interference with Tenant's use: (a) to install use, maintain repair, replace and
relocate for service to the Premises and other parts of the Building (or
either), pipes, ducts, conduits, wires and appurtenant fixtures, wherever
located in the Premises or Building, and (b) to alter or relocate any other
common facility, provided that substitutions are substantially equivalent to or
better than the Original Installations, replacements and relocations referred to
in clause (a) above shall be located so far as reasonable in the central core
area of the Building, above ceiling surfaces, below floor surfaces or within
perimeter walls of the Premises. Landlord also reserves the right, from time to
time, to: (x) change the name or street address of the Building, (y) install and
maintain signs on the exterior and the interior of the Building, and (z) possess
passkeys to the Premises.

        Landlord acknowledges that such activities as described above may
adversely affect Tenants use of the Premises and agrees to make reasonable
efforts not to interfere with Tenants use of the Property. Landlord shall not
enter the Premises to perform said activities without prior reasonable notice to
Tenant. Landlord shall, however, have the right to enter the premises in case of
an emergency or after an Event of Default, without notice to Tenant.

        2.4   PARKING. Tenant shall be entitled to park in common with other
tenants of Landlord, and receive its pro-rata share of unreserved parking
spaces. Tenant agrees not to overburden the parking facilities by utilizing more
than its pro-rata share of parking and agrees to cooperate with Landlord and
other Tenants in the use of parking facilities. Said parking spaces shall be
used for parking by vehicles no larger than full-size passenger automobiles or
pick-up trucks, herein called "Permitted Size Vehicles." Vehicles other than
Permitted Size Vehicles shall be parked and loaded or unloaded as directed by
Landlord. Landlord reserves the right, in its absolute discretion, to determine
whether parking facilities are becoming overcrowded, and in such event, to
allocate parking spaces among Tenants or to designate areas within which Tenant
must park. Tenant and Tenant's employees, visitors and customers assume all
responsibility for damage and theft to vehicles. Tenant shall provide Landlord
with the license plate numbers of all of its employees who commute by
automobile. Landlord reserves the right to cause to be towed the automobiles of
Tenant's employees, agents, customers or visitors who park outside the
designated parking areas. Tenant's rights hereunder may not be transferred.


                ARTICLE III - TERM; LANDLORD'S AND TENANT'S WORK

        3.1   TERM. The term of this Lease shall be as specified in the Basic
Lease Provisions set forth in Article 1. The term of this Lease shall also
include any fraction of a calendar month between the commencement of the Term
("Commencement Date") and the first day of the first full calendar month
thereof.




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        3.2    COMMENCEMENT DATE. The Commencement Date shall be the earlier of
(i) the date on which Landlord tenders possession of the Premises or any part
thereof or (ii) the date on which Leasehold Improvements (as set forth in
Exhibit C) are substantially completed. Substantial completion of the Leasehold
Improvements, for purposes of this provision shall mean completion of
construction sufficient for Tenant to occupy the Premises for fixturing or for
the use intended, including completion of HVAC, electrical service and floor
finishes, and Landlord's obtaining a temporary certificate of occupancy, subject
only to punchlist items and Landlord obtaining a fire certificate of occupancy
for the Premises.

               (a) Possession of the Premises shall be deemed tendered to Tenant
("Tender of Possession") when (1) the Leasehold improvements to be provided by
Landlord under this Lease are substantially completed, (2) the Building
utilities are ready for use in the Premises, and (3) Tenant has reasonable
access to the Premises. Landlord and Tenant shall execute an amendment to this
Lease, in the form attached hereto as Exhibit F, establishing the date of Tender
of Possession or the actual taking of possession by Lessee, whichever first
occurs, as the Commencement Date.

        3.3    EXTENSION OPTION. Notwithstanding anything to the contrary set
forth in the Lease, Landlord hereby grants to Tenant one (1) option (the
"Option") to extend the Term of the Lease for a period of three (3) years (the
"Option Term"). The Option must be exercised, if at all, by written notice (the
"Option Notice") delivered by the Tenant to Landlord not earlier than Twelve
(12) months nor later than NINE (9) months prior to the end of the initial Term.
Further, the Option shall not be deemed to be properly exercised if, as of the
date of the Option Notice, Tenant (i) is in default under the lease beyond
applicable grace or cure periods as set forth in this Lease, or (ii) has
assigned or sublet all or any portion of the Lease or Tenants interest therein
to any party to which a sublet or assignment is not permitted under the term of
this Lease. Provided Tenant has properly and timely exercised the Option, the
initial Term shall be extended by the Option Term, and all terms, covenants and
conditions of the Lease shall remain unmodified and in full force and effect,
except that the Rent shall be modified as set forth below.

               (a)   The Rent payable for the Option Term shall be the
"fair-market" rental rate. For the purposes of this Paragraph only,
"fair-market" rental rate shall mean the projected prevailing gross rental rate
as of the first day of the Option Term, charged to renewal tenants, for similar
rentable space situated in similar buildings located in the North Andover area.
Included with the Option Notice, Tenant shall provide Landlord with its estimate
of "fair-market" rental rate. Within Sixty (60) days of receipt of the Option
Notice, Landlord shall provide notice to Tenant, in writing Landlord's estimate
of "fair-market" rental rate. Said notification of the annual rent may include a
provision for escalation of rent during the renewal term. Tenant shall have
FIFTEEN (15) days ("Tenant's Review Period") after receipt of the Landlord's
written notice of the "fair-market" rental rate within which to accept such
"fair-market" rental rate in writing. In the event Tenant objects to the
"fair-market" rental rate submitted by Landlord, Landlord and Tenant shall
attempt in good faith to agree upon such "fair-market" rental rate, using
good-faith efforts. If Landlord and Tenant fail to reach agreement on such
"fair-market" rental rate within THIRTY (30) days following Tenant's Review
Period (the "Outside Agreement Date"), then each party's determination shall be
submitted to appraisal in accordance with the following:

                     (i) Landlord and Tenant shall each appoint one (1)
        independent appraiser who shall by profession be a real estate broker
        active over the previous five (5) year period ending on the date of such
        appointment in the leasing of commercial properties in the North Andover
        area. The determination of the appraiser shall be limited solely to the
        issue of whether Landlord's or Tenant's submitted "fair-market" rental
        rate for the Premises is closest to the actual fair-market rental rate
        for the Premises as determined by the appraisers, taking into account
        the requirements set forth above. Such decision shall be based upon the
        projected prevailing fair-market rental rate as of the commencement date
        of the Option Term. Each such appraiser shall be appointed within
        FIFTEEN (15) days after the Outside Agreement Date.




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                     (ii)   The two (2) appraisers so appointed shall within
        FIFTEEN (15) days after the date of the appointment of the last
        appointed appraiser agree upon and appoint a third appraiser who shall
        be qualified under the same criteria set forth above for the initial two
        (2) appraisers.

                     (iii)  The three (3) appraisers shall, within THIRTY (30)
        days after the appointment of the third appraiser, reach a decision as
        to whether the parties shall use Landlord's or Tenant's submitted
        "fair-market" rental rate, and shall notify Landlord and Tenant in
        writing thereof.

                     (iv)   The decision of a majority of the three (3)
        appraisers shall be binding upon Landlord and Tenant. If either Landlord
        or Tenant fails to appoint an appraiser within the time period specified
        herein above, the appraiser appointed by one of them shall reach a
        decision based upon the same procedure set forth above (i.e., by
        selecting either Landlord's or Tenant's submitted "fair-market" rental
        rate), and shall notify Landlord and Tenant thereof and such appraiser's
        decision shall be binding upon Landlord and Tenant.

                     (v)    If the two (2) appraisers fail to agree upon and
        appoint a third appraiser, both appraisers shall be dismissed and the
        matter to be decided shall be submitted to arbitration under the
        provisions of the American Arbitration Association based upon the same
        procedures set forth above (i.e., by selecting either Landlord's or
        Tenant's submitted "fair-market" rental rate).

                     (vi)   The costs of appraisal hereunder, and arbitration if
        necessary, shall be paid by Landlord and Tenant equally.

               (b)   In no event shall any rent during the Option Term fall
below the Rent in effect for the month immediately preceding the expiration of
the initial Term of the Lease.

               (c)   Landlord and Tenant hereby agree to execute an amendment to
the Lease promptly after Tenant's exercise of the Option in order to incorporate
the extension of the initial Term and the lease terms thereof into the Lease.

        3.4   LANDLORD'S WORK. Except for Landlord's Work described in the Work
Letter Agreement attached hereto as Exhibit C, the Premises shall be delivered
"AS IS", subject to all title matters, all applicable zoning, and Laws and
Insurance Regulations, as defined in Section 5.1 (a), and except as set forth in
this Lease, Landlord shall not be required to make any repairs or replacements
(hereafter jointly "Repairs") or improvements, alterations or additions
(hereafter collectively "Improvements") to the Premises. Tenant acknowledges
that Tenant has inspected (or had the opportunity to inspect) the Premises, is
satisfied with the condition thereof subject to completion of Landlord's Work.
Tenant agrees that all claims with respect to Landlord's Work shall be made
within One (1) year of the Commencement Date or, in the case of latent defects,
not later than thirty (30) days following the manifestation of such defect, and
that all claims not made within such periods shall be forever waived.

        The parties acknowledge that Landlord will be constructing certain
improvements ("Leasehold Improvements") to the Building in accordance with the
Work Letter Agreement attached hereto as Exhibit C. Landlord shall use
reasonable efforts to complete the construction of the Leasehold Improvements
and deliver the Premises on or before the anticipated Commencement Date set
forth in the Basic Lease Information. If Landlord has been unable to complete
such Leasehold Improvements and deliver the Premises on or before the
anticipated Commencement Date, Landlord shall not be liable for such failure,
such failure shall not affect the validity of this Lease. If Landlord has been
unable to construct the Leasehold Improvements or deliver the Premises because
Tenant has failed to comply with its obligations under the Work Letter Agreement
attached as Exhibit C, or if Tenant has otherwise delayed Landlord in completing
the Leasehold Improvements or obtaining any certificate or approval for same,
then the




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Commencement Date shall be the date that the Premises would have been "ready for
occupancy" but for such Tenant-caused delay. "Ready for occupancy" shall be
defined as the date upon which construction of the Leasehold Improvements would
have been substantially completed (as defined above) as reasonably determined by
Landlord and contractor(s) performing said improvements. If possession of the
Premises is not delivered to Tenant within ninety (90) days after the
anticipated Commencement Date, as the same may be extended under the terms of a
Work Letter executed by Landlord and Tenant, Lessee may, at its option, by
notice in writing to Lessor within ten (10) days after the end of said ninety
(90) day period, cancel this Lease, in which event the parties shall be
discharged from all obligations hereunder. The ninety (90) day period following
the Commencement Date before which Tenant's right to cancel this Lease accrues
under paragraph 3.4, shall be deemed extended to the extent of any Tenant delays
caused by acts or omissions of Tenant's agents, employees and contractors and as
defined in the Work Letter Agreement attached hereto as Exhibit C.

        3.5   TENANT'S WORK. Tenant shall not make nor cause to be made any
Alterations or Utility installations in, on, under or about the Premises without
Landlord's prior written consent. Tenant may, however, at its sole cost and
expense, make non-structural Alterations or Utility Installations to the
interior of the Premises (excluding the roof) without Landlord's consent but
upon notice to Landlord, so long as they are not visible from the outside of the
Premises, do not involve puncturing, relocating or removing the roof or any
existing walls, or changing or interfering with the fire sprinkler or fire
detection systems and the cumulative cost thereof during each Lease Year does
not exceed $10,000.00. Said notice to Landlord shall include a detailed
description of said work and plans therefore. Landlord shall have the
opportunity to review said notice and require reasonable modifications the
proposed Alterations or Utility Installations. Any Alterations or Utility
Installations that Tenant shall desire to make and which require the consent of
the Landlord shall be at Tenant's sole cost and expense and shall be presented
to Landlord in written form with detailed plans. Approval by Landlord shall not
be deemed or construed to mean that Tenant's Plans comply with applicable laws,
rules, regulations, ordinances, or codes. In the event that Landlord approves
Tenant's Plans, Tenant shall submit all subsequent changes or amendments thereto
to Landlord for its review and approval. If Landlord rejects Tenant's Plans,
Tenant shall promptly revise and correct the same and promptly resubmit said
plans and specifications to Landlord for its review and approval.

        Upon Landlord's approval of Tenant's Work, Tenant shall, at its sole
cost and expense, promptly perform Tenant's Work in a good and workmanlike
manner using first-class new materials and equipment, in accordance with
Tenant's Plans which have been approved by Landlord, and in accordance with the
requirements of all applicable Laws and Insurance Regulations.

        Prior to the commencement of Tenant's Work, in the event Tenant's work
will cost in excess of $10,000, Tenant shall, upon reasonable request of
Landlord, at Tenant's sole cost and expense, deliver to Landlord a performance
bond and statutory lien bond from companies reasonably acceptable (or other form
of security reasonably acceptable Landlord) in an amount equal to the estimated
cost of Tenant's Work, if requested by Landlord. Tenant shall hold Landlord free
and harmless from any liability for labor or materials supplied for such work
and for any loss in connection with Tenant's Work or any other work performed
in, on, or about the Premises, and Tenant shall keep the Premises free from
mechanic's liens of any kind by obtaining waivers therefor and removing any such
lien in accordance with Section 6.3.

        Any and all structural alterations, additions or improvements shall
become the property of Landlord promptly after installation.




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<PAGE>   7
                                ARTICLE IV - RENT

        4.1   BASE RENT AND ADDITIONAL RENT. Tenant shall pay Base Rent monthly,
in advance, on the Rent Commencement Date and on the first day of each calendar
month thereafter. Any additional sums due under the terms of this Lease
("Additional Rent") payable by Tenant shall be paid when due. If (i) Base Rent
and/or any Additional Rent is not received by Landlord or otherwise paid within
5 days of the due date, or (ii) Tenant's check is not honored, and because
actual damages result from late payments and dishonored checks are difficult to
fix, Tenant agrees to pay (a) $500.00 as liquidated damages for (i) each late
payment not made before the 5th day after the same was due, and (ii) each
dishonored check, and (b) an additional $100.00 per day after said 5th day until
said payment is made. In addition, Landlord may charge interest from the initial
due date at the rate of the lesser of 18% or the maximum legal rate on all
amounts not paid or received by Landlord within 10 days of the due date.

        Notwithstanding the above Landlord shall provide Tenant with two (2)
written notices of late payments and/or dishonored checks within any Lease Year
without penalties set forth above, provided Tenant cures the rental payment
default within five (5) days of said notice. In the event Tenant is late paying
rent in excess of twice a year, the above penalties shall apply without the
necessity of further notice from Landlord.

        Notwithstanding the fact that Base Rent may not commence until the Rent
Commencement Date, all other obligations hereunder commenced on the Commencement
Date, including without limitation, Tenant's obligation to pay Tax Rent (defined
herein), Operating Cost Rent, utilities, and the like.

        4.2   SECURITY DEPOSIT. N/A.

        4.3   ADDITIONAL RENT. Tenant shall pay to Landlord during the term
hereof, in addition to the Base Rent, Tenant's Share, as hereinafter defined, of
the amount by which all Operating Expenses, as hereinafter defined, for each
Comparison Year exceeds the amount of all Operating Expenses for the Base Year
such excess being hereafter referred to as the "Operating Cost Rent", in
accordance with the following provisions:

              (a)   "Tenant's Share" is defined, for purposes of this Lease, as
the percentage based upon the ratio between the rentable square footage of the
Premises and the rentable square footage of the space in all of the buildings
located on the Property which utilize the specific utility or service provided
by Landlord.

              (b)   "Base Year" is defined as the calendar year in which the
Lease term commences.

              (c)   "Comparison Year" is defined as each calendar year during
the term of this Lease subsequent to the Base Year; provided, however, Tenant
shall have no obligation to pay a share of the Operating Expense Increase
applicable to the first twelve (12) months of the Lease Term (other than such as
are mandated by a governmental authority, as to which government mandated
expenses Tenant shall pay Tenants Share, notwithstanding they occur during the
first twelve (12) months). Tenant's Share of the Operating Expense Increase for
the first and last Comparison Years of the Lease Term shall be prorated
according to the portion of such Comparison Year as to which Tenant is
responsible for a share of such increase. Operating Expenses shall include the
following:

                    (i)   "TAX RENT" which shall include real estate taxes,
        assessments, sales or use taxes, sewer entrance fees, and other public
        charges on or relating to the Park and the Property including, without
        limitation, the Building, other improvements, land and personalty, taxes
        on rentals, and taxes in addition to or in lieu of existing taxes,
        foreseen and unforeseen, ordinary and extraordinary, and all costs
        related to attempts to secure a refund or abatement (together called
        "Taxes"). Tenant also




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<PAGE>   8
        shall pay before the due date all taxes attributable to Tenant's signs
        or personal property, and all Tax increases resulting from the Leasehold
        Improvements or Tenant's Improvements to the Premises. Landlord's
        income, estate, succession, inheritance and transfer taxes shall be
        excluded from "Taxes"; provided, however, that if at any time during the
        Term the present system of ad valorem taxation of real property shall be
        changed so that as a substitute for, or in addition to, the whole or any
        part of the ad valorem tax on real property, there shall be assessed on
        Landlord any tax including a capital levy or other tax on the gross
        rents received with respect to the Property, or a federal, state,
        county, municipal, or other local income, franchise, excise or similar
        tax, assessment, levy or charge (distinct from any now in effect in the
        jurisdiction in which the Property is located), and whether or not now
        customary or in the contemplation of the parties, measured by or based,
        in whole or in part, upon any such gross rents, then any and all of such
        taxes, assessments, levies or charges, to the extent so measured or
        based, shall be deemed to be included within the term "Taxes".

                    Landlord shall have sole control of all tax abatement
        proceedings, and the pendency of abatement proceedings or Landlord's
        withholding of tax payments shall not affect Tenant's obligations to pay
        Taxes as provided herein. The amount of any abatement proceeds with
        respect to any year on account of which Tenant shall have made a payment
        of Tax Rent shall, after deduction therefrom of any expenses reasonably
        incurred in their collection and not included in Taxes for said year, be
        allocated to Tenant in the same proportion as was used to determine
        Tenant's payment of such Tax Rent and Landlord shall at its option
        either pay such amount to Tenant or credit such amount against monthly
        installments of Base Rent and Additional Rent next thereafter ensuing,
        except with respect to such abatement proceeds as are received after the
        end of the Tenn, with respect to which Landlord shall make payment to
        Tenant within thirty (30) days upon receipt.

                    (ii)   "OPERATING COST RENT" which shall include all costs
        and expenses of every kind and nature incurred by Landlord in operating,
        managing, equipping, lighting, cleaning, maintaining, insuring,
        repairing and replacing the Premises, the Building, the Park and the
        Property ("Operating Costs"), including without limitation, premiums for
        insurance carried with respect to the Property, (ii) compensation and
        all fringe benefits, workers' compensation insurance premiums and
        payroll taxes paid by Landlord to, for or with respect to all persons
        actually engaged in the operating, maintaining, or cleaning of the
        Building, Park or Property, (iii) steam, water, sewer, electric, gas,
        oil and telephone charges (excluding utility charges separately
        chargeable for additional or special services); (iv) code of building
        and cleaning services and equipment; (y) cost of maintenance, cleaning
        (including window cleaning) and repairs (other than repairs for which
        Landlord has received reimbursement from contractors under guaranties);
        (v) snow removal and landscaping; (vii) payments under service contracts
        with independent contractors, including security services, legal,
        accounting and other professional fees, and management fees; (viii)
        costs (including financing charges) of improvements to the Property that
        are designed to increase safety or reduce or limit increases in
        Operating Costs, are required to comply with any law imposed after the
        initial completion of the Building, or are deemed necessary or desirable
        by Landlord, all such improvements to be amortized using generally
        accepted accounting principles; and (ix) all other reasonable or
        necessary expenses paid in connection with the operation, maintenance,
        replacement and repair of the Property and properly chargeable against
        income. Any of the above services may be performed by Landlord or its
        affiliates, provided that fees for the performance of such services
        shall be reasonable and competitive with fees charged by unaffiliated
        entities for the performance of such services in comparable buildings.
        Operating Costs shall not include leasing commissions, repair costs to
        the extent paid by insurance proceeds or by any tenant or third party,
        or any tenant improvements provided for any tenant. Regardless of the
        actual percentage of occupancy of the Building, for the purpose of this
        Section 4.4, (i) the Operating Costs will be extrapolated or
        proportionately reduced as though the buildings in the Park were one
        hundred percent (100%) occupied; and (ii) in the case of any services
        that are not rendered to all building areas on a comparable basis, the
        proportion of the expense of




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        such service allocable to the Premises shall be in the same proportion
        which the rentable floor area of the Premises to which the service is
        rendered bears to the total rentable floor area to which such service is
        rendered.

                    Operating Expenses shall not include the following: (i) any
        expenses paid by any lessee directly to third parties, or as to which
        Lessor is otherwise reimbursed by any third party, other tenant or by
        insurance proceeds; (ii) the costs of correcting defects in the original
        construction of the Building; (iii) any land rent payable by Lessor
        pursuant to any land lease; (iii) any fines, penalties payable by
        Lessor, its employees or agents incurred due to the violation of any
        valid applicable laws as a result of default of negligence; (iv)
        original acquisition or construction costs relating to any expansion of
        the building; (v) any leasing commissions, tenant improvement costs, and
        advertising costs related to leasing the Building; (vi) any expenses
        incurred to supply services and/or maintenance exclusively to other
        lessees of the Building; (vii) expenses incurred due to the violation of
        any lessee (other than Lessee) of any terms and conditions of the other
        leases in the Office Building Project

        Operating Cost Rent and Tax Rent shall be paid to Landlord monthly with
Base Rent in the amount which Landlord estimates, from time to time, will
represent Tenant's Pro Rata Share of Operating Costs Rent and Tax Rent Increases
over the base year. Landlord shall notify Tenant of its actual Pro Rata Share
within ninety (90) days of the end of each calendar year (provided Landlord's
failure to so notify Tenant shall not reduce Tenant's liability when such notice
is issued), and any excess paid by Tenant shall be applied to Tenant's next
Operating Cost or Tax Rent payment and any deficiency shall be paid within
fifteen (15) days of such notice.

        In addition to Operating Cost Rent and Tax Rent, Tenant shall reimburse
Landlord for Tenant's "Direct Reimbursable Expenses." "Direct Reimbursable
Expenses" means operating costs of any nature which can be attributable directly
to the operating, maintenance, repair and/or replacement of the premises of an
individual tenant. Such expenses shall be due and payable by Tenant within
fifteen (15) days of receipt of a bill.

        Tenant shall have sixty (60) days after receipt of Landlord's statement
of Tenant's actual pro-rata share to notify Landlord of any objections they have
to such statement or of their intention to review supporting documentation for
such statement. If Tenant does not so notify Landlord, such statement shall
conclusively be deemed correct and Tenant shall have no right thereafter to
dispute or review support for such statement, any item therein, or the
computation of Operating Costs. If Tenant does so notify the Landlord within the
sixty (60) day period, Tenant may, after reasonable notice to Landlord, and
during normal business hours, inspect Landlord's records concerning operating
expenses for the preceding calendar year in question. In no event may such
inspection be made by a person or firm which is being paid on a contingency fee
basis. Tenant shall have six (6) months from the date of receipt of Landlord's
statement to complete their review of the supporting documentation and notify
Landlord of all objections, if any, to such statement. Landlord and Tenant
hereby agree that Tenant will submit in writing to Landlord on or before the end
of said six-month period, all objections to Landlord's statement. Landlord and
Tenant hereby agree that after said six-month period, Tenant has no further
rights to review any supporting documentation to Landlord's statement. Pending
resolution of any dispute, Tenant shall nevertheless continue to pay the amounts
required by the provisions of this Article 4.

        If Landlord and Tenant are unable to resolve any dispute relating to the
objections to Landlord's statement, a certification as to the proper amount(s)
shall be made by an independent certified public accountant appointed by
Landlord and Tenant. The certification shall be final and conclusive of the
disputes relating to the Landlord's statement.




                                        9

<PAGE>   10
        If Tenant disputes Landlord's statement and Landlord designates a
certified public accountant to perform an audit, the accountant shall have the
power to, and shall inquire into and determine, not only whether or not Tenant
was overcharged for any Operating Expenses, but whether or not Tenant was
undercharged for any Operating Expenses. The certification shall what Tenant's
Share of Operating Expenses should have been had Landlord strictly complied with
the provisions of this Lease. If Landlord overcharged Tenant for Tenant's Share
of Operating Expenses, the amount of the overcharge shall be returned to Tenant
within thirty (30) days following the issuance of the certification. If Tenant
was undercharged for Tenant's Share of Operating Expenses, Tenant shall pay the
amount of such undercharge to Landlord within thirty (30) days following the
issuance of the certification.

        Should the certification show errors in excess of ten percent (10%) of
the Operating Expenses, then Landlord shall be responsible for all reasonable
fees incurred by Tenant with respect to the audit but in no event shall Landlord
be responsible for the amount of any such fees which is in excess of the total
amount of the overcharge determined by the accountant. Should the certification
show errors of less than three percent (3%) of the Operating Expenses, then
Tenant shall be responsible for all the reasonable fees incurred by Landlord
with respect to the audit. Should the certification show errors of between three
percent (3%) and ten percent (10%) of the Operating Expenses, then each party
shall be responsible for all fees incurred by it with respect to the dispute.

        Tenant's rights and remedies with respect to any errors and/or
overcharges made by Landlord with respect to Operating Expenses shall be limited
to those expressly set forth in this Article. Neither Tenant nor Tenant's agents
or representatives shall reveal the results of any inspection or audit performed
pursuant to the provisions of this Article to any third party except as may be
required in connection with obtaining any amounts due to Tenant hereunder.


            ARTICLE V - TENANT'S COVENANTS AND LANDLORD'S OBLIGATIONS

        5.1    GENERAL COVENANTS. In addition to Tenant's other Lease covenants,
Tenant shall, at its expense:

               (a)   Use the Premises solely and continuously for the Permitted
Use and for no other purpose, procure all required licenses and permits, and not
use the Premises in violation of any laws, ordinances, orders or regulations of
any public authority or of any insurer, Board of Fire Underwriters, or similar
insurance rating bureau having jurisdiction over the Premises, including without
limitation, the State Building Code and the Americans With Disabilities Act of
1990, as amended, and any and all regulations promulgated thereunder (hereafter
collectively "Laws and Insurance Regulations") or in a manner which may be
injurious to or adversely affect the general character of the Premises and not
conduct any auction, bankruptcy or similar sale thereon;

               (b)   comply with sign criteria imposed by applicable 
governmental authorities;

               (c)   pay, as they become due, all charges for utilities for the
Premises and pay for all taxes imposed upon or relating to Tenant's business and
Tenant's personal property;

               (d)   keep the Premises, including, without limitation, doors,
windows, plumbing, electrical, and all fixtures and equipment appurtenant to the
Premises, in a neat, clean, sanitary condition and in good order and repair
(making replacements as necessary); replace broken glass with the same quality
glass; paint (exterior and interior) and refurbish the Premises and restore or
replace the floor covering at reasonable intervals, and in any event at such
times as may reasonably be required to keep the Premises attractive in




                                       10

<PAGE>   11
appearance; not overload, damage or deface the Premises; properly store and
dispose of all trash, and maintain service contracts with reputable companies
for any janitorial services.

               (e)   make Improvements and Repairs of whatever nature required
by Laws and Insurance Regulations to the extent such improvements or
replacements are related solely to the Tenant's particular use of the Premises;

               (f)   pay for all Repairs to the Premises, the Building, the
Park, and the Property required by Tenant's act or omission or that of Tenant's
Affiliates;

               (g)   not act in any manner which prevents Landlord or Tenant
from obtaining, or makes void or voidable, any insurance, or creates extra
premiums for or increases the rate of insurance, and if Tenant causes extra
premiums or increased rates, Tenant will pay the increased cost upon demand;

               (h)   not act in any manner which prevents Landlord or Tenant
from obtaining, or causes the revocation of, any government license, permit, or
authority, and if as a direct or indirect result of Tenant's business an
addition to or change in the same is required by Laws or Insurance Regulations,
Tenant shall pay for the addition or change;

               (i)   abide by reasonable rules and regulations made by Landlord
from time to time.

        5.2    ENVIRONMENTAL COVENANTS.

               (a)   DEFINITION. As used in this Lease, the term "Hazardous
Material" means any flammable items, explosives, radioactive materials,
hazardous or toxic substances, material or waste or related materials, including
any substances defined as or including in the definition of "hazardous
substances", "hazardous wastes", "infectious wastes", "hazardous materials" or
"toxic substances" now or subsequently regulated under any federal, state or
local laws, regulations or ordinances including, without limitation, oil,
petroleum-based products, paints, solvents, lead, cyanide, DDT, printing inks,
acids, pesticides, ammonia compounds and other chemical products, asbestos, PCBs
and similar compounds, and including any different products and materials which
are subsequently found to have adverse effects on the environment or the health
and safety of persons. The term "Hazardous Materials Laws" shall mean, without
limitation, each and every law, rule, order, statute or regulation described
above in this Section, together with (i) any amendments thereto or regulations
promulgated thereunder, and (ii) any other laws pertaining to the protection of
the environment or governing the use, release, storage, generation or disposal
of Hazardous Materials, whether now or existing or hereafter enacted or
promulgated.

               (b)   GENERAL PROHIBITION. Tenant shall not cause or permit any
Hazardous Material to be generated, produced, brought upon, used, stored,
treated, discharged, released, spilled or disposed of on, in, under or about the
Premises, Building, Park, or property. Tenant shall indemnify, defend and hold
Landlord harmless from and against any and all actions (including, without
limitation, remedial or enforcement actions of any kind, administrative or
judicial proceedings, and orders or judgments arising out of or resulting
therefrom), costs, claims, damages (including, without limitation, punitive
damages), expenses (including, without limitation, attorneys', consultants' and
experts', fees, court costs and amounts paid in settlement of any claims or
actions), fines, forfeitures or other civil, administrative or criminal
penalties, injunctive or other relief (whether or not based upon personal
injury, property damage, or contamination or adverse effects upon, the
environment, water tables or natural resources), liabilities or losses arising
from a breach of this prohibition by Tenant or Tenant's Affiliates.

               (c)   NOTICE. In the event that Hazardous Materials are
discovered upon, in, or under the Premises, Building, Park, or Property, and any
governmental agency or entity having jurisdiction over the




                                       11

<PAGE>   12
Premises, Building, the Park, or Property requires the removal of such Hazardous
Materials, Tenant shall be responsible for removing those Hazardous Materials
arising out of or related to its use or occupancy of the Premises, Building, the
Park, or Property, as the case may be, by Tenant or Tenant's Affiliates.
Notwithstanding the foregoing Tenant shall not take any remedial action without
first notifying Landlord of Tenant's intention to do so and affording Landlord
the opportunity to protect Landlord's interest with respect thereto. Tenant
immediately shall notify Landlord in writing of: (i) any spill, release,
discharge or disposal of any Hazardous Material in, on or under the Premises, or
any portion thereof, (ii) any notice, enforcement, clean-up, removal or other
governmental or regulatory action instituted, contemplated or threatened (if
Tenant has notice thereof) pursuant to any Hazardous Materials Laws; (iii) any
claim made or threatened by any person against Tenant or the Premises, Building,
Park, or Property relating to Hazardous Materials; and (iv) any reports made to
any governmental agency or entity arising out of or in connection with any
Hazardous Materials in, on, under or about or removed from the Property,
including any complaints, notices, warnings, reports or asserted violations in
connection therewith.

               (d)   SURVIVAL. The respective rights and obligations of Landlord
and Tenant under this subsection shall survive the expiration or earlier
termination of this Lease.

        5.3    LANDLORD'S COVENANTS. Landlord, subject to reimbursement pursuant
to Section 4.3, shall (i) maintain or arrange to maintain the Common Areas in
good condition subject to reasonable wear and tear, keeping them reasonably
clear of snow and ice and free of rubbish and trash (ii) subject to Article
VIII, perform capital repairs to the structural columns and the roof of the
Building, unless such repair is necessitated by the act or omission of Tenant or
Tenant's Affiliates, and (iii) furnish services, and supplies as set forth on
EXHIBIT C. Landlord warrants to Tenant that to Landlord's actual knowledge the
Premises, in the state existing on the date that the Lease term commences, but
without regard to alternations or improvements made by Tenant or the use for
which Tenant will occupy the Premises, does not violate any covenants or
restrictions of record, or any applicable building code, regulation, law or
ordinance in effect on such Lease term Commencement Date. Subject to the terms
and conditions set forth herein, Landlord agrees that Tenant is entitled to and
shall have, the quiet enjoyment of the Premises.

                       ARTICLE VI - CONDITION OF PREMISES

        6.1    IMPROVEMENTS. Except as Specifically set forth herein, Landlord
shall have no obligation to improve the Premises and shall deliver the Premises
in its "AS-IS" condition. Except as provided in Section 3.4 of this Lease,
Tenant may not make structural or non-structural Improvements to the Premises
without Landlord's prior written consent, which shall not be unreasonably
withheld or delayed. At the end of the Tenn, except to the extent Tenant is
directed by Landlord to remove any Improvements that Landlord required to be
removed at the time Landlord consented to installation of the improvement and to
repair damage relating to such removal, the Premises shall remain in the altered
condition with all Improvements.

        6.2    FIXTURES: YIELD-UP. Except as Landlord directs in writing, Tenant
shall remove its personal property signs and trade fixtures, and peaceably
yield-up the Premises, broom-clean and in good order, repair, and condition at
the end of the Tenn, with all Repairs, including painting and patching to the
Premises required by such removal, having been made and all utility lines left
exposed or unconnected having been capped. If Tenant fails to remove its
property or to make the Repairs by the end of the Term, Landlord may remove and
store Tenant's property in a public warehouse at Tenant's expense or sell same
at public auction, and make the Repairs, and Tenant promptly shall reimburse
Landlord for its costs.

        6.3    MECHANIC'S LIENS. Tenant shall immediately discharge any
mechanic's, materialmen's or other lien against the Premises, Building, Park, or
Property and/or Landlord's interest therein arising out of




                                       12

<PAGE>   13
any payment due, or purported to be due, for any labor, services, materials,
supplies, or equipment alleged to have been furnished to or for Tenant.


                             ARTICLE VII - INSURANCE

        7.1    INSURANCE. Tenant shall maintain at its sole expense, the
following coverages:

               (a)   COMMERCIAL GENERAL LIABILITY INSURANCE covering the insured
against claims of bodily injury, personal injury and property damage arising out
of Tenants operations, assumed liabilities or use of the Premises, Building,
Park, or Property, including the performance by Tenant of the indemnities set
forth herein, with a combined single limit of not less than $3,000,000.00 (or
such higher limits as or may be reasonably required by Landlord based upon
inflation, increased liability awards, recommendations of Landlord's mortgagee
("Mortgagee") or professional insurance advisors.

               (b)   CASUALTY INSURANCE. 100% replacement cost all-risk,
extended coverage property insurance covering the Tenant's personal property,
Leasehold Improvements, and all other improvements, which insurance shall
contain a sprinkler leakage endorsement and a rent loss endorsement which shall
provide for the payment of Base Rent and Additional Rent for a period of at
least one year.

               (c)   BOILER AND MACHINERY INSURANCE. If Tenant shall receive
Landlord's prior written consent to operate on the Premises a boiler or other
pressured vessels, Tenant shall, as a pre-condition to installing the same,
place and maintain Boiler Insurance with limits of liability in an amount not
less than $250,000 per occurrence or as needed, and provide coverage for the
full replacement value thereof.

               (d)   WORKER'S COMPENSATION/EMPLOYER'S LIABILITY INSURANCE.
Worker's Compensation Insurance or similar statutory coverage containing
statutorily prescribed limits and Employer's Liability with limits reasonably
acceptable to Landlord.

        If (i) any insurance policy carried by Landlord with respect to the
Property shall be canceled or cancellation shall be threatened or the coverage
thereunder reduced or threatened to be reduced in any way by reason of the use
or occupation of the Premises or any part thereof by Tenant, and (ii) Tenant
fails to remedy the condition giving rise to cancellation, threatened
cancellation or reduction of coverage within forty-eight (48) hours after notice
thereof, such failure shall be deemed a default under this Lease, and Landlord
may exercise its option to either terminate this Lease or to enter upon the
Premises and attempt to remedy such condition, in which event Tenant shall pay
immediately to Landlord the costs associated with such termination or entry and
attempt to remedy as Additional Rent. Landlord shall not be liable for any
damage or injury caused to any property of Tenant or of others located in the
Premises as a result of such an entry.

        7.2    TENANT'S RISK. Except as modified by statute, all merchandise,
furniture, fixtures and property which may be on or about the Premises,
Building, the Park, or Property shall be at the sole risk and hazard of Tenant.

        7.3    GENERAL REQUIREMENTS. All insurance policies required to be
procured by Tenant hereunder shall be with companies qualified to do business in
Massachusetts and acceptable to Landlord, and shall name Landlord, Landlord's
mortgagee(s), and any other party designated by Landlord, as insured parties on
casualty policies and additional named insureds on liability policies. In
addition, all liability insurance obtained by Tenant shall be (a) primary
insurance as to all claims thereunder and provide that any insurance carried by
Landlord is not excess and is non-contributing with any insurance of Tenant; (b)
contain cross liability endorsements or a severability of interest clause
acceptable to Landlord, (c) be written on an



                                       13


<PAGE>   14
occurrence basis; and (d) specifically cover the liability assumed by Tenant
under this Lease including, but not limited to, Tenant's obligations under
Section 7.4. Tenant shall deliver a copy of the policies or certificates of all
insurance to Landlord prior to the earlier of entry on the Premises or the
Commencement Date, and copies of the new policies or new certificates not later
than 30 days prior to the expiration of each policy. Each policy shall provide
(and the certificate shall evidence) that it will not expire, or be canceled or
modified without 30 days prior written notice to Landlord and, if Landlord
requests, to Landlord's mortgagee(s).

        7.4    INDEMNITY. Tenant shall indemnify and hold harmless Landlord and
its agents, Landlord's master ground landlord, if any, partners and lenders,
from and against any and all claim for damage to the person or property of
anyone or any entity arising from Tenants use of the Premises, Building and
Park, or from the conduct of Tenants business or from any activity, work or
things done, permitted or suffered by Tenant in or about the Premises or
elsewhere and shall further indemnify and hold harmless Landlord from and
against any and all claims, costs and expenses, including, but not limited to,
loss of rents and/or damages, costs, liens, judgments, penalties, loss of
permits, attorneys' and consultants' fees, expenses and/or liabilities arising
out of, involving, or in connection with, the occupancy of the Premises by
Tenant, arising from any breach or default in the performance of any obligation
on Tenant's part to be performed under the terms of this Lease, or arising from
any act or omission of Tenant or any of Tenant's agents, contractors, employees,
or invitees, and from and against all costs, attorneys fees, expenses and
liabilities incurred by Landlord as the result of any such use, conduct,
activity, work, things done, permitted or suffered, breach, default or
negligence, and in dealing reasonably therewith, including but not limited to
the defense or pursuit of any claim or any action or proceeding involved
therein; and in case any action or proceeding be brought against Landlord by
reason of any such matter, Tenant upon notice from Landlord shall defend the
same at Tenant's expense by counsel reasonably satisfactory to Landlord and
Landlord shall cooperate with Tenant in such defense. The foregoing shall
include, but not be limited to, the defense or pursuit of any claim or any
action or proceeding involved therein, and whether or not (in the case of claims
made against Landlord) litigated and/or reduced to judgment. Landlord need not
have first paid any such claim in order to be so indemnified. Tenant, as a
material part of the consideration to Landlord, hereby assumes all risk of
damage to property of Tenant or injury to persons, in, upon or about the
Premises, Buildings and Park arising from any cause and Tenant hereby waives all
claims in respect thereof against Landlord.

        7.5    WAIVER OF SUBROGATION. Landlord and Tenant release each other and
each other's officers, directors, employees and agents from liability or
responsibility for any loss or damage to their respective property to the extent
of actual net insurance proceeds received (or to the extent said loss would have
been covered if the party had complied with the provisions of this Lease). This
release shall apply to the parties and anyone claiming through or under the
parties by way of subrogation or otherwise, even if the occurrence was caused by
the fault or negligence of a party or anyone for whom a party is responsible.
Landlord and Tenant each agree that, to the extent it is required to maintain
insurance policies hereunder, its policies will include such a provision if
available without extra cost, or if the other party pays the extra cost, and
each promptly shall notify the other of any extra cost.

        7.6    LANDLORD'S INSURANCE. Landlord shall obtain and keep in force
during the term of this Lease a policy or policies of insurance covering loss or
damage to the Property improvements, but not Tenants personal property,
fixtures, equipment or tenant improvements (other than initial tenant
improvements), in the amount of the full replacement cost thereof, as the same
may exist from time to time, providing protection against all perils included
within the classification of fire, extended coverage, vandalism, malicious
mischief plate glass, and such other perils as Landlord deems advisable or may
be required by a lender having a lien on the Property. The policies required by
hereby shall contain such deductibles as Landlord or the aforesaid lender may
determine. In the event that the Premises shall suffer an insured loss, the
deductible amounts under the applicable insurance policies shall be deemed an
Operating Expense.




                                       14

<PAGE>   15
Tenant shall not do or permit to be done anything which shall invalidate the
insurance policies carried by Landlord. Tenant shall pay the entirety of any
increase in the property insurance premium for the Property over what it was
immediately prior to the commencement of the term of this Lease if the increase
is specified by Landlord's insurance carrier as being caused by the particular
nature of Tenants occupancy (aside from general office use) or any act or
omission of Tenant.


                   ARTICLE VIII - CASUALTY AND EMINENT DOMAIN

        8.1    DAMAGE. If the Premises become untenantable in whole or part
because of (a) fire or other casualty covered by insurance ("Casualty"), or as
the result of a taking of the Premises (or any building thereon) in connection
with the exercise of any power of eminent domain, condemnation, or purchase
under threat or in lieu thereof ("Taking"), then unless the Lease is terminated
in accordance with Section 8.7, Landlord, with reasonable dispatch (but subject
to delays for adjustment of insurance proceeds or taking awards, as the case may
be, and causes beyond Landlord's reasonable control), shall repair the damage in
the event of a Casualty so that the Premises are in substantially the same
condition as on delivery of possession (and in the event of a Taking, shall
restore the balance of the Premises not so taken to substantially the same
condition as is reasonably feasible), all subject to rights of mortgagees,
zoning laws, and building codes then in existence, and provided Landlord shall
not be required to expend more than the net insurance proceeds Landlord receives
for damage to the Premises or the net taking award attributable to the Premises.
"Net" means the insurance proceeds or taking award less all costs and expenses,
including adjusters and attorney's fees, of obtaining the same. Tenant
immediately shall give written notice to Landlord of any damage to the Premises.

        8.2    TERMINATION RIGHTS. If (a) the Premises or Building are damaged 
to the extent of 10% or more of its insurable value, or by a risk not covered by
insurance with a cost to repair in excess of $100,000.00, or the damage is of a
character that it cannot reasonably be repaired within sixty (60) days of the
date on which repair work commences, or (b) if 25% or more of either (i) the
floor area of the Building, or (ii) the land which constitutes the Property is
subject to a taking, Landlord may elect to terminate this Lease by Written
notice to Tenant within 30 days after the damage or within 6 months of the date
on which the condemning authority has the right to possession ("Taking Date') in
which case the Lease shall terminate as of the Taking Date. If the entire
Premises are taken by eminent domain, except for temporary use, this Lease shall
terminate automatically as of the Taking Date.

        8.3    ABATEMENT. If a portion of the Premises is damaged or taken,
except for temporary use, and this Lease is not terminated, the Base Rent shall
be reduced proportionately based on the area of the Premises damaged and
therefore not used by Tenant or taken until the earlier of when Landlord's
Repairs to the Premises are completed or Tenant begins using the damaged area.

        8.4    TAKING FOR TEMPORARY USE. If the Premises are taken for temporary
use, this Lease and Tenant's obligations shall continue, except to the extent
the taking renders compliance impossible or impracticable.

        8.5    DISPOSITION OF AWARDS. Except for any separate award for Tenant's
movable trade fixtures or relocation expenses all taking awards to Landlord or
Tenant shall be Landlord's property without Tenant's participation.




                                       15


<PAGE>   16
                       ARTICLE IX - DEFAULTS AND REMEDIES

        9.1    TENANT'S DEFAULT. The following conditions shall be considered a
"Default" by Tenant:

               (a)   failure to pay Base Rent, Additional Rent or any other
charge within five days of the due date, subject to Article 4.1 of this Lease;

               (b)   Tenant's leasehold estate is taken by execution or other
process of law; or Tenant is liquidated, dissolved, commits an act of
bankruptcy, is declared bankrupt or insolvent according to law or admits in
writing its inability to pay debts generally as they become due, or an
assignment of Tenant's property is made for the benefit of creditors or a
receiver, guardian, conservator, trustee or assignee, or any other similar
officer or person is appointed to take charge of any part of Tenant's property;
or any reorganization or similar proceedings are commenced by or against Tenant
under any bankruptcy or insolvency law and not dismissed within 30 days from its
commencement, or any court enters an order providing for the modification of
rights of Tenant's creditors;

               (c)   vacating of the Premises or closing for business for an
aggregate period during the Term exceeding 180 days except for fires and
unavoidable casualties;

               (d)   a Transfer without Landlord's prior written consent;

               (e)   failure to perform or observe any other Lease terms or
covenants for a period of 30 days after notice, or if same shall reasonably take
longer than 30 days, if Tenant fails to commence same promptly and to complete
same with due diligence and in any event within 60 days from the notice; or

               (f)   any other breach for which the Lease gives Landlord the
right of termination.

        If Tenant Defaults, Landlord may at any time either (i) terminate this
Lease by written notice effective on the date of the notice or on any date
specified in the notice, or (ii) without demand or notice, re-enter take
possession and repossess the Premises and, with a court order and at Tenant's
risk, expel Tenant and those claiming under Tenant and remove, store and sell
their effects at public action, all without prejudice to any remedies for
arrearages or preceding Defaults. The net proceeds of any sale shall be applied
to sums due to Landlord from Tenant and the balance paid to Tenant. Tenant
waives all statutory rights (including rights of redemption) to the extent such
rights may be lawfully waved. With or without terminating this Lease, Landlord
may re-let all or any part of the Premises from time to time for periods, at
such rental, and upon the terms and conditions as Landlord deems advisable, and
may make Improvements and Repairs to the Premises. No re-entry or taking of
possession by Landlord shall terminate this Lease unless Landlord gives a
written notice of such intention to Tenant, nor shall Landlord's right to re-let
constitute an obligation to re-let or to mitigate damages.

        9.2    DAMAGES. Tenant's liability and obligations under this Lease
shall survive termination or repossession, and Tenant shall pay as current
damages the Base Rent, Additional Rent and other sums up to what would have been
the end of the Term in the absence of the termination or repossession, with a
credit for the net proceeds, if any, Landlord receives from any reletting of the
Premises, after deducting all of Landlord's reasonable expenses in connection
with the reletting including, without limitation, expenses of preparing the
Premises for the reletting. Tenant shall pay the current damages to Landlord on
the days Base Rent would have been payable if not for the termination or
repossession. In addition, and notwithstanding any Lease provision or the
termination of this Lease, Tenant shall reimburse Landlord for any free rent and
construction allowance, and all expenses and liabilities incurred by Landlord in
connection with Tenant's Default including without limitation brokerage
commissions, reasonable attorneys' fees and alteration costs.




                                       16

<PAGE>   17
        After any termination or repossession, whether or not Landlord has
collected any current damages, Tenant shall pay to Landlord, at Landlord's
option and on demand, liquidated final damages in lieu of all current damages
beyond the date final damages are paid. The final damages shall be the amount by
which (i) all rent and other charges which would be payable from the date to
which Tenant paid current damages through what would have been the unexpired
Term exceeds (ii) the then market rental value of the Premises for the same
period. If any law validly limits the amount of final liquidated damages to less
than described above, Landlord shall be entitled to the maximum amount legally
allowed.

        9.3    LANDLORD'S SELF-HELP. If Tenant Defaults, Landlord may, at its
option, without waiving its right to terminate this Lease or its claim for
damages, cure the Default, and Tenant shall reimburse Landlord for any amount
paid or contractual liability incurred by Landlord in doing so; provided
Landlord may immediately cure any default or failure by Tenant to perform any
Lease obligation if the cure or performance is reasonably necessary to protect
the Premises or Landlord's interests, or to prevent injury or damage to persons
or property.

        9.4    LANDLORD'S DEFAULT. Landlord shall not be deemed to be in default
hereunder unless its default continues for 10 days, or such additional time as
is reasonably required to correct its default after Tenant has given written
notice to Landlord specifying the nature of the alleged default.


                            ARTICLE X - SUBORDINATION

        10.1  SUBORDINATION. Provided Tenant is provided with a commercially
reasonable non-disturbance agreement, Tenant's rights and interests under this
Lease shall be (i) subject and subordinate to any existing or future mortgages,
deeds of trust, overlease, or similar instruments covering the Premises and to
all advances, modifications, renewals, replacements, and extensions thereof
("Mortgages"), or (ii) if the Mortgagee elects, prior to the lien of any present
or future Mortgagee. Tenant further shall attorn to and recognize any successor
Landlord, whether through foreclosure or otherwise, as if the successor Landlord
were the originally named Landlord. Tenant concurrently shall give Mortgagee the
same notices given to Landlord, and Mortgagee shall have the same opportunity
and rights as is available to Landlord to cure a default provided Mortgagee
shall have an additional thirty (30) days after the expiration of Landlord's
cure period within which to commence a cure or such longer period as may be
reasonably necessary. Mortgagee's curing of any of Landlord's default shall be
treated as performance by Landlord.

        10.2   REQUEST BY MORTGAGEE. If a Mortgagee or prospective Mortgagee
requests any Lease modification which does not have a material adverse effect on
Tenant's rights, Tenant will enter into a written modification agreement in
recordable form (which shall have the same force as a Lease amendment) if the
Mortgagee forecloses or takes similar action.


                      ARTICLE XI - MISCELLANEOUS PROVISIONS

        11.1   PARTIES BOUND. Except as otherwise provided, the Lease agreements
and conditions to be performed and observed by Landlord or Tenant shall bind and
inure to the heirs, legal representatives, successors and assigns of each,
provided no reference to Tenant's successors and assigns will constitute a
consent to a Transfer by Tenant. If Tenant consists of more than one person or
entity, or if there is a guarantor, then all such persons, entities and
guarantors shall be jointly and severally liable and the word "Tenant," as used
in this Lease, including Article IX includes such person, entities, and
guarantors. The word "Landlord" means only the owner, or the tenant if this
Lease becomes subject to an overlease, or the mortgagee in possession of the
Premises such that, all prior Landlords, including Landlord, shall be relieved
of all Landlord covenants and obligations accruing after a transfer. If the
entity which holds Landlord's




                                       17

<PAGE>   18
interest in this Lease is a trust, then the Landlord obligations shall be
binding upon the trustees of said trust, as trustees and not individually, and
not upon the trust estate.

        11.2   LANDLORD'S LIABILITIES AND ADDITIONAL RIGHTS.

               (a)   Landlord shall have no obligation or liability with respect
to or in any way connected with the Premises, the Building, the Park, the
Property, or services to be provided from same, except to the extent
specifically set forth in this Lease. The obligations of Landlord set forth in
this Lease do not constitute personal obligations of the Landlord, or trustees,
partners, directors, officers, or shareholders of Landlord, and Tenant shall not
seek recourse against the Landlord, trustees, individual partners, directors
officers, or shareholders of Landlord or any of their personal assets for
satisfaction of any liability in respect to this Lease except as otherwise set
forth in Section 11.2(c) below. Landlord shall not be deemed to have committed a
breach of any repair obligations of Landlord hereunder unless it makes repairs
negligently or fails to commence repairs within a reasonable time after Landlord
receives notice from Tenant, and Landlord's liability in any case shaft be
limited to the cost of making the required repairs.

               (b)   Landlord shall not be liable for indirect or consequential
damages for any reason, or for any inconvenience, interruption or consequences
resulting from the failure of utilities or any service, making repairs,
improvements or resulting from leaks of steam, gas, electricity, water, or any
other substance from pipes, wires or other conduits, or from the bursting or
stoppage thereof, or from leaks of water, snow, or rain.

               (c)   Tenant agrees for itself and each succeeding holder of
Tenant's interest, or any portion thereof, that any judgment, decree or award
obtained against Landlord, or any succeeding owner of Landlord's interest, which
is related to this Lease or the Property, whether at law or in equity, shall be
satisfied out of Landlord's equity in the Premises, and further agrees to look
only such assets and to no other assets of Landlord for satisfaction.

               (d)   Landlord reserves the right at any time or times within the
Term and without charge, abatement or reduction in rent (i) to examine and to
show the Premises at reasonable times; (ii) to perform such work as may be
required by this Lease, any public authority, or to facilitate making repairs or
improvements to the Building, the Property or any portion thereof provided that
unless any such work is of an emergency nature, Landlord shall give reasonable
notice and shall use reasonable efforts to minimize interference with Tenant's
operations; and (iii) to enter upon, and use portions of the Premises for the
foregoing purposes.

               (e)   Landlord shall have no liability to Tenant for inconve- 
nience, annoyance, or injury to business resulting from Landlord's repairs or
improvements made hereunder except as set forth in this Lease.

        11.3 HOLDING OVER. If Tenant or anyone claiming under it holds over
after end of the Term, the party shall, prior to Landlord's acceptance of rent,
be a Tenant at sufferance, and, after Landlord's acceptance of rent, be a Tenant
at will subject to the provisions of this Lease insofar as the same may be made
applicable to a tenancy at will; provided that Tenant shall pay Base Rent for
the period of such tenancy at 200% of the highest rate of Base Rent payable
during the Term, and, in addition, Tenant shall be liable for all damages
incurred by Landlord (including consequential damages) as a result of the
holding over.

        11.4   QUIET ENVIRONMENT. Provided Tenant timely pays all rent and
performs and observes the terms, conditions and covenants of the Lease, Tenant
may peaceably and quietly have, hold and enjoy the




                                       18

<PAGE>   19
Premises as provided in the Lease, without hindrance or molestation from
Landlord or anyone claiming legally under Landlord, subject to the terms of this
Lease and any instruments having priority.

        11.5   NO BROKERAGE. Tenant warrants and represents that it has dealt
with no broker in connection with this Lease except the Broker identified herein
(if any). Tenant agrees to defend and indemnify Landlord against any brokerage
claims related to this Lease other than by the Broker.

        11.6   CERTIFICATES. Within 10 days after Landlord's request, Tenant
shall deliver to Landlord or to any prospective Mortgagee or purchaser (a) an
estoppel certificate in recordable form stating such information as Landlord
reasonably requests, and (b) such financial statements as are available to the
public to verify the net worth of Tenant or any Transferee, and Tenant
represents and warrants that each such financial statement shall be true and
accurate as of the date thereof.

        11.7   NOTICES. Any notice, consent, or other communication relating to
this Lease shall be given in writing and by hand, by registered or certified
mail or overnight express mail such as "Federal Express", postage or charges
prepaid, to the other party's Notice Address or for Tenant to the Premises, to
such other address or addresses as may be designated by the party by notice, and
if to a Mortgagee, to such address as the Mortgagee shall designate.

        11.8   NO WAIVER. Landlord's failure to complain of any Tenant act or
omission shall not be deemed a waiver of any of Landlord's rights. Landlord's
waiver, express or implied, of any breach of this Lease shall not be deemed a
waiver of a breach of any other provision or a consent to any subsequent breach
of the same or any other provision. Landlord's consent to or approval to any
action on one occasion shall not be deemed a consent to or approval of any other
action or to such action on any subsequent occasion. Tenant's payment or
Landlord's acceptance of a lesser amount than is due from Tenant to Landlord
shall not be deemed anything but payment on account and Landlord's acceptance of
a check for a lesser amount with an endorsement or statement thereon or upon a
letter accompanying the check that the lesser amount is payment in full shall
not be deemed an accord and satisfaction, and Landlord may accept the check
without prejudice to recover the balance due or pursue any other remedy. All of
Landlord's rights and remedies under this Lease or by operation of law, either
at law or in equity, for any breach shall be distinct, separate, cumulative and
non-exclusive and shall not be deemed inconsistent with each other.

        11.9   FORCE MAJEURE. With the exception of the payment of money, if any
party's performance of any act is delayed, or prevented because of strikes,
lockouts, labor troubles, inability to procure materials, power failures,
restrictive Laws, riots, insurrection, war, or other causes beyond such party's
reasonable control, then said performance shall be excused for the period of the
delay and any time period shall be extended for an equivalent period.

        11.10  RECORDING. Tenant shall not record this Lease, but may record a
notice thereof in the form attached hereto as Exhibit G.

        11.11  WAIVER OF JURY TRIAL. LANDLORD AND TENANT HEREBY WAIVE TRIAL BY
JURY IN ANY ACTION, PROCEEDING, OR COUNTERCLAIM BROUGHT BY EITHER OF THE PARTIES
HERETO AGAINST THE OTHER, OR IN RESPECT OF ANY MATTER WHATSOEVER ARISING OUT OF
OR IN ANY WAY CONNECTED WITH THIS LEASE.

        11.12 PARAGRAPH HEADINGS. All paragraph headings are for convenience and
reference only, and shall not be held to explain, modify, amplify or aid in the
construction, interpretation or meaning of the provisions of this Lease.




                                       19


<PAGE>   20
        11.13  GOVERNING LAW. This Lease shall be governed by the laws of the
Commonwealth of Massachusetts.

        11.14  SEVERABILITY: CONSTRUCTION AND INTERPRETATION. If any Lease term
or provision or the application thereof to any person or circumstance is invalid
or unenforceable, the remainder of this Lease, or the application of the term or
provision to other persons or circumstances shall not be affected, and the Lease
shall be valid and be enforced to the fullest extent permitted by law. If any
Lease provision is capable of two constructions, then the provision shall have
the meaning which renders it valid.

        11.15  WHEN LEASE BECOMES BINDING; ENTIRE AGREEMENT. Landlord's
employees or agents have no authority to make or agree to make a lease or any
other agreement or undertaking and the submission of this document for
examination and negotiation does not constitute an offer to lease, or a
reservation of or option for, the Premises, and this document shall become
effective and binding only upon the execution and delivery by both Landlord and
Tenant. All negotiations, considerations, representations, and understandings
between Landlord and Tenant are incorporated herein, and no oral statements or
prior or contemporaneous written matter, whether by the parties or otherwise,
which is not specifically incorporated herein shall be of any force or effect.

        11.16  ASSIGNMENT AND SUBLETTING.

               (a)   LANDLORD'S CONSENT REQUIRED. Tenant shall not voluntarily
or by operation of law assign, transfer, mortgage, sublet, or otherwise transfer
or encumber all or any part of Tenant's interest in the Lease or in the
Premises, without Landlord's prior written consent, which Landlord shall not
unreasonably withhold. Landlord shall respond to Tenant's request for consent
hereunder in a timely manner and any attempted assignment transfer, mortgage,
encumbrance or subletting without such consent shall be void, and shall
constitute a material default and breach of this Lease without the need for
notice to Tenant under Section IX. "Transfer" within the meaning of this Section
11.17 shall include the transfer or transfers aggregating: (a) if Tenant is a
corporation, more than fifty percent (50%) of the voting stock of such
corporation, (except in the case that Tenant is corporation whose stock is
publicly traded),or (b) if Tenant is a partnership, more than fifty percent
(50%) of the profit and loss participation in such partnership.

               (b)   TENANT AFFILIATE. Notwithstanding the provisions of
paragraph 11.16 (a) hereof, Tenant, upon written notice to Landlord may assign
or sublet the Premises, or any portion thereof, without Landlord's consent to
any corporation which controls, is controlled by or is under common control with
Tenant, or to any corporation resulting from the merger or consolidation with
Tenant or to any person or entity which acquires all the assets of Tenant as a
going concern of the business that is being conducted on the Premises, all of
which are referred to as "Tenant Affiliate"; provided that before such
assignment shall be effective, (a) said assignee shall assume, in full, the
obligations of Tenant under this Lease and (b) Landlord shall be given written
notice of such assignment and assumption. Any such assignment shall not, in any
way, affect or limit the liability of Tenant under the terms of this Lease even
if after such assignment or subletting the terms of this Lease are materially
changed or altered without the consent of Tenant, the consent of whom shall not
be necessary.

               (c)   TERMS AND CONDITIONS APPLICABLE TO ASSIGNMENT AND
SUBLETTING. Regardless of Landlord's consent, the following terms and conditions
shall apply to any subletting by Tenant of all or any part of the Premises and
shall be deemed included in all subleases under this Lease whether or not
expressly incorporated therein:

                     (1)   Regardless of Landlord's consent, no assignment or
                     subletting shall release Tenant of Tenant's obligations
                     hereunder or alter the primary liability of Tenant





                                       20

<PAGE>   21
                     to pay the rent and other sums due Landlord hereunder
                     including Tenant's Share of Operating Expense Increase, and
                     to perform all other obligations to be performed by Tenant
                     hereunder.

                     (2)   Landlord may accept rent from any person other than
                     Tenant pending approval or disapproval of such assignment.

                     (3)   Neither a delay in the approval or disapproval of
                     such assignment or subletting, nor the acceptance of rent,
                     shall constitute a waiver or estoppel of Landlord's right
                     to exercise its remedies for the breach of any of the terms
                     or conditions of this paragraph 11.16 of this Lease.

                     (4)   If Tenant's obligations under this Lease have been
                     guaranteed by third parties, then an assignment or
                     sublease, and Landlord's consent thereto, shall not be
                     effective unless said guarantors give their written consent
                     to such sublease and the terms thereof.

                     (5)   The consent by Landlord to any assignment or
                     subletting shall not constitute a consent to any subsequent
                     assignment or subletting by Tenant or to any subsequent or
                     successive assignment or subletting by the sublessee.
                     However, Landlord may consent to subsequent subletting and
                     assignments of the sublease or any amendments or
                     modifications thereto without notifying Tenant or anyone
                     else liable on the Lease or sublease and without obtaining
                     their consent and such action shall not relieve such
                     persons from liability under this Lease or said sublease;
                     however, such persons shall not be responsible to the
                     extent any such amendment or modification enlarges or
                     increases the obligations of the Tenant or sublessee under
                     this Lease or such sublease.

                     (6)   In the event of any default under this Lease,
                     Landlord may proceed directly against Tenant, any
                     guarantors or any one else responsible for the performance
                     of this Lease, including the sublessee without first
                     exhausting Landlord's remedies against any other person or
                     entity responsible therefor to Landlord, or any security
                     held by Landlord or Tenant.

                     (7)   Landlord's written consent to any assignment or
                     subletting of the Premises by Tenant shall not constitute
                     an acknowledgment that no default then exists under this
                     Lease of the obligations to be performed by Tenant nor
                     shall such consent be deemed a waiver of any then existing
                     default except as may be otherwise stated by Landlord at
                     the time.

                     (8)   The discovery of the fact that any financial
                     statement relied upon by Landlord in giving its consent to
                     an assignment or subletting was materially false shall, at
                     Landlords election, render Landlord's said consent null and
                     void.

                     (9)   In connection with any proposed assignment of the
                     Lease or Sublease of all or any portion of the Premises,
                     Tenant shall deliver to Landlord, for Landlord's review and
                     written approval, all such information concerning the
                     proposed assignee or sublessee as Landlord may reasonably
                     require or request, including, but not limited to, any
                     financial statements or other financial information and all
                     terms of the proposed assignment or sublease.





                                       21

<PAGE>   22
                     (10)  Notwithstanding anything to the contrary set forth in
                     the Lease, Tenant hereby assigns and transfers to Landlord
                     One Hundred Percent (100%) of all of Tenant's interest in
                     and to all rent and other consideration which is in excess
                     of the then-current Rent, after deduction of any
                     commissions or tenant improvement funds actually paid by
                     Tenant arising from any assignment or sublease of the
                     Premises hereafter made by Tenant and Landlord may collect
                     such rent and other consideration and apply same toward
                     Tenant's obligations under the Lease.

                     (11)  Landlord shall not, by reason of this or any other
                     assignment of such sublease to Landlord nor by reason of
                     the collection of the rents from a sublessee, be deemed
                     liable to the sublessee of any failure of Tenant to perform
                     and comply with any of Tenant's obligations to such
                     sublessee under such sublease. Tenant hereby irrevocably
                     authorizes and directs any such sublessee, upon receipt of
                     a written notice from Landlord stating that a default
                     exists in the performance of Tenant's obligations under
                     this Lease, to pay to Landlord the rents due and to become
                     due under the sublease. Tenant agrees that such sublessee
                     shall have the right to rely upon any such statement and
                     request from Landlord, and that such sublessee shall pay
                     such rents to Landlord without any obligation or right to
                     inquire as to whether such default exists and
                     notwithstanding any notice from or claim from Tenant to the
                     contrary. Tenant shall have no right or claim against said
                     sublessee or Landlord for any such rents so paid by said
                     sublessee to Landlord.

                     (12)  Subject to the provisions of paragraph 11.16(b), no
                     sublease entered into by Tenant shall be effective unless
                     and until it has been approved in writing by Landlord. In
                     entering into any sublease, Tenant shall use only such form
                     of sublease as is reasonably satisfactory to Landlord, and
                     once approved by Landlord, such sublease shall not be
                     changed or modified without Landlord's prior written
                     consent. Any sublessee shall, by reason of entering into a
                     sublease under this Lease, be deemed, for the benefit of
                     Landlord, to have assumed and agreed to conform and comply
                     with each and every obligation herein to be performed by
                     Tenant other than such obligations as are contrary to or
                     inconsistent with provisions contained in a sublease to
                     which Landlord has expressly consented in writing.

                     (13)  In the event Tenant shall default in the performance
                     of its obligations under this Lease, Landlord at its option
                     and without any obligation to do so, may require any
                     sublessee to attorn to Landlord, in which event Landlord
                     shall undertake the obligations of Tenant under such
                     sublease from the time of the exercise of said option to
                     the termination of such sublease; provided, however,
                     Landlord shall not be liable for any prepaid rents or
                     security deposit paid by such sublessee to Tenant or for
                     any other prior defaults of Tenant under such sublease.

                     (14)  No sublessee shall further assign or sublet all or
                     any part of the Premises without Landlord's prior written
                     consent.

                     (15)   With respect to any subletting to which Landlord has
                     consented, Landlord agrees to deliver a copy of any notice
                     of default by Tenant to the sublessee. Such sublessee shall
                     have the right to cure a default of Tenant within three (3)
                     days after service of said notice of default upon such
                     sublessee, and the sublessee shall




                                       22


<PAGE>   23
                     have a right of reimbursement and offset from and against
                     Tenant for any such defaults cured by the sublessee.

               (d)   LANDLORD'S EXPENSES. In the event Tenant shall assign or
sublet the Premises or request the consent of Landlord to any assignment or
subletting or if Tenant shall request the consent of Landlord for any act Tenant
proposes to do then Tenant shall pay Landlord's reasonable costs and expenses
incurred in connection therewith, including attorneys', architects', engineers'
or other consultants' fees.

               (e)   PROCEDURE AND CONDITIONS FOR CONSENT. In the event Tenant
wishes to sublet or assign the Premises, or any portion thereof, the following
procedure shall apply:

                     (1)   Tenant shall submit in writing to Landlord (A) the
               name of the proposed sublessee or assignee, (B) a statement
               describing the nature of the business to be carried on in the
               Premises, (C) a copy of the proposed sublease or assignment,
               including all terms and conditions thereof, (D) Landlord's lease
               application form, completed by the proposed assignee or
               sub-Tenant, (E) financial statements for the proposed assignee or
               sublessee, which shall include, at a minimum, prior year and year
               to date (current to within six months) balance sheets, income and
               expense statements and sources and uses of cash statements, and
               (F) such other reasonable financial information regarding such
               sublessee or assignee as Landlord shall reasonably request.

                     (2)   At any time within twenty (20) days after Landlord's
               receipt of all the information specified in Paragraph
               11.17(e)(1), Landlord may, by written notice to Tenant, elect to:
               (A) sublet or assign the Premises upon the same terms and
               conditions as those offered to the proposed sublessee or
               assignee; or (B) cancel and terminate this Lease with respect to
               the portion of the Premises proposed to be sublet or assigned,
               with a proportionate abatement of rent payable hereunder, or (C)
               consent to such sublease or assignment, in which event such
               consent may be conditioned upon the agreement by Tenant to pay
               over to Landlord all or any portion of the amount by which any
               rent or other consideration received by Tenant from the sublessee
               or assignee exceeds the amount of rent actually payable by Tenant
               to Landlord pursuant to this Lease during the period of the
               proposed assignment or sublease; or (D) withhold Landlord's
               consent. If Landlord fails to respond to Tenant's request for
               consent within thirty (30) days after receipt of all of the
               information specified in Paragraph 11.17(e)(1) above, Landlord's
               consent will be deemed to have been given.

        It shall be reasonable for Landlord to consider in deciding whether to
consent to an assignment or sublease, any or all of the following factors
regarding the proposed assignee or sublessee: (A) whether the proposed assignee
or sublessee has continuing financial strength, (B) proposed use of the Premises
by the assignee or sublessee, including the applicability of any covenants not
to compete undertaken by Landlord to other lessees in the Building, whether made
before or after execution of this Lease; (C) the proposed assignee's or
sublessee's business reputation; (D) the tenant mix within the Building; (E) the
applicability and effect upon any percentage rental provisions; and (F) the
business capability, experience and other qualifications of the proposed
assignee or sublessee.

                           [INTENTIONALLY LEFT BLANK]




                                       23


<PAGE>   24
        11.17  EXECUTION. This Lease may be executed in any number of original
counterparts. Each fully executed counterpart shall be deemed an original.

                                          LANDLORD:  NAM Partners, L.P.

                                          ______________________________________



                                          By: Robert Mashaal, Manager NAM Mills,
                                              L.L.C., its General Partner






                                          TENANT: Brooktrout Technology, Inc., a
                                                  Massachusetts corporation



By: /s/ Robert C. Leahy                   By:
    -------------------------------           ----------------------------------
    (Authorized Officer)                      (Authorized Officer)



Print Name: Robert C. Leahy               Print Name:
            -----------------------                   --------------------------


Title: Vice President                     Title:
       ----------------------------              -------------------------------




                                       24

<PAGE>   25
                                    EXHIBIT A

                                PLAN OF PREMISES










                                       25


<PAGE>   26
                                    EXHIBIT A

                                PLAN OF PREMISES

This plan is intended only to show the general layout of the property or a part
thereof. Lessor reserves the right to alter, vary, add to or omit, in whole or
in part, any structures, and/or improvements, and/or common areas, and/or land
areas shown on this plan. All measurements and distances are approximate. This
plan is not to be scaled.

                                     [Graph]








                                       26


<PAGE>   27
                                    EXHIBIT A

                                PLAN OF PREMISES

This plan is intended only to show the general layout of the property or a part
thereof. Lessor reserves the right to alter, vary, add to or omit, in whole or
in part, any structures, and/or improvements, and/or common areas, and/or land
areas shown on this plan. All measurements and distances are approximate. This
plan is not to be scaled.


                                     [Graph]



















                                       27


<PAGE>   28
                                    EXHIBIT B

                          LEGAL DESCRIPTION OF PROPERTY

















                                       28


<PAGE>   29
                                    EXHIBIT B

                          LEGAL DESCRIPTION OF PROPERTY

                               [Legal Description]






















                                       29


<PAGE>   30
                                    EXHIBIT C

                              WORK LETTER AGREEMENT


        This Work Letter Agreement shall set forth the terms and conditions
relating to the construction of the Tenant Improvements in the Premises. This
Work Letter Agreement is essentially organized chronologically and addresses the
issues of the construction of the Premises, in sequence, as such issues will
arise during the actual construction of the Premises. All references in this
Work Letter Agreement to Articles or Sections of "this Lease" shall mean the
relevant portion of Articles 1 through 11 of the Lease to which this Work Letter
Agreement is attached as Exhibit C and of which this Work Letter Agreement forms
a part. The terms, covenants and conditions set forth herein are intended to and
shall have the same force and effect as if set forth at length in the body of
the Lease.

        Landlord and Tenant hereby acknowledge and agree that certain
improvements shall be constructed by Landlord in the Premises (the "Tenant
Improvements"), in accordance with the procedures set forth herein.

        1.   BRIEF DESCRIPTION OF TENANT IMPROVEMENTS TO BE CONSTRUCTED BY
LANDLORD. Landlord shall construct the Tenant Improvements in substantial
conformance with mutually agreeable space plan and specifications attached
hereto as Exhibit C-1. Any and all other improvements to the Premises shall be
made at Tenant's sole cost and expense.

        2.   PLANS AND SPECIFICATIONS.

             (a)   Within ten (10) business days of mutual execution of the
Lease, Landlord shall deliver the Final Plans to Tenant, and within five (5)
business days after Tenants receipt thereof, Tenant shall notify Landlord in
writing of either Tenants approval or disapproval thereof, including any
corrections or changes required by Tenant to the Final Plans. Landlord shall
deliver to Tenant revised Final Plans which incorporate Tenant's proposed
changes, provided such proposed changes (i) are reasonable, (ii) are made in
good-faith and with particularity and precision and (iii) are in conformance
with Exhibit C- I attached hereto. In the event Landlord does not receive
written notice from Tenant for any requested changes to the Final Plans within
the time period specified herein, the Final Plans shall be conclusively deemed
approved by Tenant.

             (b)   Landlord shall not be required to furnish professional
interior design services to Tenant and shall not be required to pay for
professional interior design services engaged by Tenant. Further, Tenant's
interior furnishings, i.e., specification, supply and installation of furniture,
furnishings, and moveable equipment shall be the sole responsibility of Tenant.
All of Tenant's installation of interior furnishings and equipment shall be
coordinated with any work being performed by Landlord in the Premises or
elsewhere in the Building in such manner as to maintain harmonious labor
relations and not damage the Building or the Premises or interfere with Building
operations; provided, however, that without Landlord's prior consent, Tenant may
not install any interior furnishings in advance of the date on which the
Premises are Ready for Occupancy.

        3.   CONSTRUCTION. Following final approval of the Final Plans, Landlord
shall rely upon the Final Plan and use commercially reasonable efforts to
complete the Tenant Improvements described in the Final Plans prior to the
scheduled anticipated Commencement Date of as set forth the Lease. Landlord's
contractor (and its subcontractors) shall construct the Tenant Improvements in
accordance with the Final Plans, (a) unless a Change Order is made in accordance
with Section 4 of this Agreement, and (b) subject to delays as described in
Section 5 of this Agreement and delays due to governmental regulation, unusual




                                       30


<PAGE>   31
scarcity of or inability to obtain labor or materials, labor difficulties,
casualty or other causes reasonably beyond Landlord's control.

        4.   CHANGE ORDERS. If the Tenant requests any change, addition or
alteration to the Final Plans or in Landlord's construction and completion of
the Tenant Improvements ("Changes"), Landlord shall promptly give Tenant an
estimate of the cost of such Changes and the resulting delay in the delivery of
the Premises to Tenant Within two (2) days after Tenant's receipt of such
written estimate from Landlord, Tenant shall give Landlord written notice
indicating whether or not Tenant elects to proceed with any such Changes. If
Tenant elects to proceed with such Changes and if, and only if, Landlord
approves such Changes, Landlord shall, at Tenants sole cost land expense,
promptly make such Changes. If Tenant elects not to proceed with such Changes or
fails to timely notify Landlord of Tenant's election within such two (2) day
period, Landlord shall complete the Tenant Improvements in the Premises without
making such Changes. In the event Tenant desires to proceed with such changes,
no different work shall be done unless and until Tenant shall first execute a
written agreement concerning the scope of the revised work or materials desired
by Tenant, cost of such work or materials and the effect of any resulting delay
(each, a "Change Order"). Further, a Change Order shall be required and executed
in the event Tenant selects materials or quantities that differ from those
specified in the Final Plans. All costs for labor and materials resulting from a
Change Order, including the cost of all plans prepared pursuant thereto, shall
be billed directly to Tenant by Landlord upon completion of construction of the
Tenant Improvements, and Tenant shall pay the amount of such bill as Additional
Rent within thirty (30) days after receipt thereof. All Work required pursuant
to a Change Order shall be undertaken by Landlord's contractor or its
subcontractor and not by Tenant.

        5.   TENANT'S DELAYS. To the extent that the Commencement Date of the
Term has not occurred because Landlord was delayed in substantially completing
the Tenant Improvements as a result of the following (collectively, "Tenant
Delays"):

                 (i)   Tenant's failure to complete any action item on or before
        the due date which is the responsibility of Tenant to complete, or

                 (ii)  Tenant's request for Changes or the construction of such
        Changes by Landlord, or

                 (iii) Tenant's request for materials, finishes, or
        installations other than those specified and reasonably provided by
        Landlord, or

                 (iv)   Any delay by Tenant in making any payment(s) to
        Landlord, or

                 (v)    Any act or failure to act by Tenant, Tenant's employees,
        agents, architects, independent contractors, consultants and/or any
        other person performing or required to perform services on behalf of
        Tenant, then

             then, notwithstanding anything to the contrary set forth in the
        Lease or this Work Letter Agreement and regardless of the actual date of
        the Substantial Completion of the Premises, the Lease Commencement Date
        shall be deemed to be the date the Lease Commencement Date would have
        occurred if no Tenant delay or delays, as set forth above, had occurred.

        If Landlord's contractor is required to work beyond the anticipated
Commencement Date as a result of Tenant-caused delays (then Tenant shall be
responsible for and shall pay to Landlord upon completion of the Tenant
Improvements the additional supervisory and general conditions costs incurred by
Landlord.




                                       31


<PAGE>   32
        6.   UNAVOIDABLE DELAYS. If the performance by Landlord or any act
required herein or elsewhere in the Lease is prevented or delayed by reason of
strikes, lockouts, labor disputes, governmental delays, acts of God, fire,
floods, earthquake, epidemics, freight embargoes, unavailability of materials
and supplies, development moratoriums imposed by any governmental authority, or
any other cause beyond the reasonable control of Landlord (including any "Tenant
Delay" (as hereinabove defined)), Landlord shall be excused from performance for
the time period equal to the time period of the prevention or delay.

        7.   TENANT IMPROVEMENT ALLOWANCE FOR VOICE AND DATA NETWORK. Landlord
shall contribute a "Tenant Improvement Allowance" for Tenant to utilize for the
design and construction of its Voice and Data Network, as proposed in that
certain proposal from Mahon Communications Corporation, dated November 5, 1998
and attached hereto as Exhibit C-2, in an amount which may equal, but shall not
exceed, Fifty Thousand dollars ($50,000.00). The Tenant Improvement Allowance
shall be disbursed by Landlord within 15 days following receipt of Tenant's
requests for disbursement which shall include invoices and conditional lien
releases (if applicable) which shall be approved by Tenant or Tenant's designer.
Any such Improvements shall be made in accordance with Paragraph 3.4 of the
Lease. Landlord and Tenant hereby acknowledge and agree that Landlord shall not
be obligated to construct and complete any work related to the Tenant's voice
and data network as set forth in the above referenced proposal, and Landlord
shall not be responsible, in any manner whatsoever, for the design and
construction of Tenant's voice and data network or any improvements within the
scope of work set forth in above referenced proposal. Tenant hereby agrees to
indemnify and defend Landlord and hold Landlord harmless from and against any
and all claims, costs, expenses or liability (including, without limitation,
Tenant's failure to obtain any necessary permits, approvals or certificates from
the applicable governmental authorities and/or actual attorney's costs and fees,
and court costs), arising from Tenant's design, construction and operation
Tenant's voice and data network in, on or about the Premises.

        Tenant shall not be entitled to receive any payment or credit, or any
offset or deduction against any monetary obligation of Tenant under the Lease,
for any portion of the Tenant Improvement Allowance which is not expended by
Landlord.

        8.   WINDOW TINTING. In addition to the work to be performed by
Landlord, as set forth above, Landlord shall install window tinting in
Building #12.

                                        LANDLORD:  NAM Partners, L.P.



                                        ______________________________________


                                        By: Robert Mashaal, Manager NAM Mills,
                                            L.L.C., its General Partner







                                       32


<PAGE>   33
                                        TENANT: Brooktrout Technology, Inc.



                                        By: 
                                            ---------------------------------
                                            (Authorized Officer)


                                        Print Name: -------------------------


                                        Title: ------------------------------



                                        BY: /s/ Robert C. Leahy
                                            ----------------------------------
                                            (AUTHORIZED OFFICER)


                                        Print Name: ROBERT C. LEAHY
                                                    --------------------------



                                        Title: VICE PRESIDENT
                                               -------------------------------











                                       33


<PAGE>   34
                                     [GRAPH]




















                                       34


<PAGE>   35
                                    EXHIBIT D

                               LANDLORD'S SERVICES


I.      JANITORIAL Landlord will provide no Janitorial or Cleaning Services in
        the Premises

II.     HEATING, VENTILATING, AIR CONDITIONING

        A.     Landlord shall furnish space heating and cooling as normal
               seasonal changes may require to provide reasonably comfortable
               space temperature and ventilation for occupants of the Premises
               under normal business operation, daily from 8:00 a.m. to 8:00
               p.m., Saturdays and Sundays 10:00 a.m. to 3:00 p.m., holidays
               excepted.

               If Tenant shall require air conditioning or heating or
               ventilation outside the hours and days above specified, Landlord
               shall furnish such service at Tenant's expense.

        B.     The air conditioning system is based upon an occupancy of not
               more than one person per 150 square feet of usable floor area,
               and upon a combined lighting and standard electrical load not to
               exceed 3.5 watts per square foot of usable area. In the event
               Tenant exceeds this condition or introduces onto the Premises
               equipment which overloads system, and/or in any other way causes
               the system not adequately to perform their proper functions,
               supplementary systems, may at Landlord's option be provided by
               Landlord at Tenant's expense.

III.    WATER

        A.     Landlord shall furnish cold water at temperatures supplied by the
               water mains for drinking, lavatory, and toilet purposes and hot
               water for lavatory purposes only from regular building supply at
               prevailing temperatures

V.      ELECTRICAL SERVICE

        Tenant to pay all charges associated with electricity to and for the
        Premises.












                                       35

<PAGE>   36
                                    EXHIBIT E

                              RULES AND REGULATIONS



1.      The purpose of this Exhibit is hereby agreed to be: To adopt a workable
        code of regulations protecting the Landlord and Tenant of the Building
        toward the goal of creating a harmonious atmosphere of high professional
        competence in the Property.

2.      Landlord agrees that Tenant is entitled to and shall have the quiet
        enjoyment of the Premises.

3.      Tenant and Tenant's employees shall not loiter in the entrance or
        corridors of the Building, or in any way obstruct the sidewalks, halls,
        stairways and elevators, and shall use the same only as a means of
        passage to and from their respective offices.

4.      The water closets, urinals and other plumbing shall be used for the
        purpose for which they were constructed and no rubbish, newspapers or
        other substances of any kind shall be thrown into them.

5.      All electric and telephone wiring shall be installed as directed by
        Landlord and boring or cutting of floors and partitions for wires will
        not be permitted, except with the written consent of Landlord.

6.      Tenant shall not install or use any machinery in the Premises which may
        cause any unreasonable noise, jar or tremor to the floors or walls, or
        which by its weight might injure the floors of the Building. Landlord
        shall prescribe the weight, size and position of all files, safes and
        heavy equipment used in the building, which in all cases shall stand on
        a wood or metal base of size and type designated by Landlord. All damage
        to the Building caused by installing or removing any safe, furniture,
        equipment or other property shall be repaired at the expense of Tenant.

7.      Tenant and Tenant's agents and employees shall not play any musical
        instrument including radio and television, in a loud or objectionable
        manner, or make or permit any improper noises in the Building, or
        interfere in any way with other tenants or those having business with
        them or bring into or keep within the Building any animal, bird or
        vehicle.

8.      Tenant shall not conduct any auction on the Premises.

9.      All furniture, equipment and height shall be moved into and out of the
        Building only during such hours as shall be reasonably approved by and
        under the supervision of Landlord. Landlord will not be responsible for
        loss of or damage to any furniture, equipment or freight from any cause.

10.     All keys to the Premises or the Building shall be returned to Landlord
        upon the termination of Tenant's lease. Tenant shall not change the
        locks or install other locks on doors of the Premises unless otherwise
        provided in the Lease or approved in advance by Landlord.

11.     Landlord reserves the right to exclude or expel from the Building any
        person who, in the judgment of the Landlord, is intoxicated or under the
        influence of liquor or drugs, or who shall do any act in violation of
        the rules and regulations of the Building.

12.     Landlord reserves the right to close and keep locked all entrance and
        exit doors of the Building during hours Landlord may reasonable deem
        advisable for the adequate protection of the property. Except to those
        having keys to the Building, use of the Building before 7:00 a.m. or
        after 6:00 p.m., on Monday through Saturday, or at any time during
        Sundays or legal holidays shall be permissive









                                       36

<PAGE>   37
        and subject to the rules and regulations Landlord may reasonably
        prescribe. Landlord assumes no responsibility and shall not be liable
        for any damage resulting from the entry of any authorized or
        unauthorized person to the Building.

13.     Landlord shall have the right to prohibit any advertising by any agent
        which in Landlord's opinion, tends to impair the reputation of the
        Building or its desirability as a Building for offices, and upon written
        notice from Landlord, such Tenant shall refrain from or discontinue such
        advertising.

14.     No Tenant will install blinds, shades, awnings or other form of inside
        or outside window covering, or window ventilators or similar devices
        without the prior written consent of Landlord.

15.     Tenant shall give Landlord prompt notice of any accidents to or defects
        in the water pipes, gas pipes, electric lights and fixtures, heating
        apparatus or any other service equipment.

16.     Tenant shall not use, keep or permit to be used or kept any foul or
        noxious gas or substance in the Premises, or permit or suffer the
        Premises to be occupied or used in a manner offensive or objectionable
        to Landlord or other occupants of the Building by reason of noise, odors
        and/or vibrations, or interfere in any way with other tenants or those
        having business therein.

17.     No cooking shall be done or permitted by Tenant on the Premises, except
        in areas specifically designed for the purpose, without the consent of
        Landlord, nor shall the Premises be used for the storage of merchandise,
        for washing clothes, for lodging, or for any improper, objectionable or
        immoral purposes.

18.     Tenant shall not use or keep in the Premises of the building any
        kerosene, gasoline or inflammable or combustible fluid or material, or
        use any method of heating or air conditioning other than that permitted
        or approved.

19.     Tenant shall see that the doors of the Premises are closed and securely
        locked before leaving the Premises, and must observe strict care and
        caution that all water faucets or water apparatus are shut off before
        Tenant or Tenant's employees leave, and that all electricity shall
        likewise be carefully shut off, so as to prevent waste or damage, and
        for any default or carelessness Tenant shall make good all injuries
        sustained by other tenants or occupants of the Building or Landlord.

20.     No commercial vending machine or machines of any description shall be
        installed, maintained or operated upon the Premises without the written
        consent of Landlord.

21.     Tenant shall not disturb, solicit or canvass any occupant of the
        Building and shall cooperate to prevent same.

22.     All parking authorized by the Lease shall be for the personal
        transportation to and from the Building of Tenant and its employees, and
        not for long-term (i.e., for more than forty-eight hours) storage of
        automobiles or for short- or long-term storage of boats, trailers,
        recreational vehicles, motorcycles or other vehicles or equipment.

23.     From time to time it may become advantageous to the Project for Landlord
        to make further revisions to these rules and regulations. To the extent
        consistent with and permitted by the Lease, Landlord reserves the right
        to make such revisions by giving notice to Tenant.

24.     There shall be no smoking allowed within the Building and the entry
        areas of the Building. Smoking shall be permitted only in areas
        designated by Landlord.



                                       37


<PAGE>   38
25.     Tenant's building operating hours shall be 8:00AM to 8:00PM Monday
        through Friday and 10:00AM through 3:00PM on Saturdays and Sundays. HVAC
        charges shall be $15 per hour for any requests made at any time other
        than Tenant's building operating hours.











                                       38

<PAGE>   39
                                    EXHIBIT E

                     LEASE COMMENCEMENT MEMORANDUM/AMENDMENT



        This Lease Commencement Memorandum/Amendment is executed on this ____
day of _________, 1999 by and between by and between NAM Partners, L.P, and
Brooktrout Technology, Inc. The terms, covenants and conditions set forth herein
are intended to and shall have the same force and effect as if set forth at
length in the body of the Lease. To the extent that the provisions of this
Amendment are inconsistent with any provisions of the Lease, the provisions of
this Addendum shall supersede and control. Lessor and Lessee hereby agree and
amend the Lease as follows:

        1.     Possession of the Premises has been tendered to Lessee.

        2.     Commencement Date and Term. Pursuant to Paragraph 3 of the Lease,
the Commencement Date of the Lease is hereby established for all purposes as and
the term, of the Lease shall expire on ____________.

                                LANDLORD: NAM Partners, L.P.


                                _______________________________________________
                                By: Robert Mashaal, Manager NAM Mills, L.L.C., 
                                its General Partner



                                TENANT: BROOKTROUT TECHNOLOGY, INC.


                                By:____________________________________________
                                       (Authorized OFFICER)


                                Print Name:____________________________________
                                Title:_________________________________________




                                By:____________________________________________
                                       (Authorized OFFICER)

                                Print Name:____________________________________
                                Title:_________________________________________







                                       39

<PAGE>   40
                                   EXHIBIT C-1




                      PRICING NOTES, AS SUPPLEMENT TO PLAN
                      INTERSPEED JOB - NORTH ANDOVER MILLS
                         DRAWING DATED: DECEMBER 8, 1998



1.      Drop ceiling to be installed at following areas only:
        -    Eight private offices
        -    Demo Room
        -    Tech Support Lab
        -    Small Conference Room
        -    Large Conference Room
        -    Computer Room & P.C. Storage

2.      Flooring to be building standard level loop carpet, glue direct, unless
        noted otherwise on drawing. Exception 1) Computer Room to receive Anti
        Static Tile (ESD), Exception 2) Lounge Area to receive VCT.

3.      All new wall surfaces to receive smooth coat and paint

4.      All drop ceiling areas to receive building standard 2' x 4' fluorescent
        fixtures

5.      All areas not receiving drop ceiling will use existing lighting system

6.      Computer Room will contain approximately 12 desk top type computers.
        This room needs to be climate controlled, so if a drop ceiling is
        required, contractor to price accordingly. Further, provide adequate
        power for 12 computer systems.

7.      Provide One power drop per 4-6 work stations throughout all areas of
        workstations

8.      Caged Stock Rooms require 8' high wire-way partition enclosure as per
        the drawing. Openings to be sliding gates no less than 6' wide. These
        rooms need minimal wall electricity - one duplex per hard wall in each

9.      Manufacturing lab to receive a total of 12 power drops, locations to be
        determined

10.     Provide 2 duplex outlets and one mud ring per private office

11.     Provide 4 duplex outlets in large conference room, evenly spread, and
        one mud ring

12.     Provide 2 duplex outlets in small conference room, evenly spread, and
        one mud ring

13.     Provide 4 duplex outlets in demo room, evenly spread, and one mud ring

14.     Provide 1 duplex outlet in reception area in floor as shown, and one mud
        ring

15.     Provide one 4-plex floor outlets in center of Large Conference Room,
        Small Conference Room & Demo Room (only Large Conference Room and Demo
        Room are shown on plan).





                                       40


<PAGE>   41
16.     Provide one unisex shower, in location to be determined, but in close
        proximity to either the existing restrooms or the new counter and sink -
        see note

17.     All new walls to be 10', drywall capped

18.     No improvements are required, other than carpet, at Growth Workstations

19.     Millwork in Demo Room to be building standard Lowers only.

20.     Millwork in Equipment Room to be building standard Lowers and Uppers.




Price to exclude Telcom/Data except for mud rings/pull strings where indicated











                                       41

<PAGE>   42
                                   EXHIBIT C-1
                        TENANT IMPROVEMENT SPECIFICATIONS
                      INTERSPEED JOB - NORTH ANDOVER MILLS
                                DECEMBER 15,1998


________________________________________________________________________________

ITEM                                       DESCRIPTION
________________________________________________________________________________

Cabinets                    Plastic laminate with plastic laminate counter tops.
                            Shelves shall be Melamine. Plastic laminate shall be
                            Wilsonart or equal.
________________________________________________________________________________

 Vestibule addition         Kawneer (or equal) bronze aluminum framing with 1/4"
                            clear glass, tempered as required by code. Interior
                            "roof" of vestibule shall be gypsum.
________________________________________________________________________________

 Side light glazing         1/4" clear, tempered where required by code.
________________________________________________________________________________

 Interior doors             5 ply solid core red oak, 3' x 7' with clear field
                            finish
________________________________________________________________________________

 Door frames                Painted hollow metal
________________________________________________________________________________

 Door hardware              Standard ADA compliant lever hardware by Schlage,
                            Arrow or Falcon. Ball bearing hinges, standard door
                            stops. No closers
________________________________________________________________________________

 Drywall                    3-5/8" metal studs with one layer of 5/8" gypsum
                            each side. Walls are 10' and braced to each other.
                            Sound insulation at conference rooms only. Short
                            walls at Manufacturing to receive gypsum cap.
________________________________________________________________________________

 Acoustic ceiling           Armstrong 2 x 4 square edge lay in fissure tile in
                            standard grid.
________________________________________________________________________________

 Vinyl composition tile     Armstrong standard colors
________________________________________________________________________________

 Static disapative tile     VPI standard colors
________________________________________________________________________________

 Carpet                     Shaw Industries 26 ounce loop pile "Potential", "On
                            Line", of "Sea Island" lines.
________________________________________________________________________________

 Vinyl base                 Johnsonite standard colors
________________________________________________________________________________

 Paint                      Standard Benjamin Moore colors, primer plus two
                            coast. No polynix.
________________________________________________________________________________




                                       42


<PAGE>   43
                                   EXHIBIT C-2

                        Mahon Communications Corporation




November 5, 1998






Mr. Todd Pearlman
Yale, Properties
6356 Greenwich Dr.
Suite 230
San Diego, CA 92122

RE:  Highspeed voice and Data Network
     For Interspeed at North Andover Mills

Todd,

MCC is providing the following Scopes of work for your review.

Scopes of work and quantities are calculated from Beth Loepers drawings and
Interspeeds needs.

With the height of the ceiling in some areas, MCC is recommending modular
furniture to come in contact with either the I-Beams, outside walls or interior
hardwalls.

MCC can not install power poles of the lengths that would be needed in those
areas, therefore MCC is requesting, if needed building owner to supply Conduit
Access to those areas.

During MCC's walk through with Interspeed on October 26, 1998, it was noted that
the office space was a non plenum environment allowing for PVC cabling. If this
is to change please notify MCC to adjust pricing to plenmun cable.

Scope 1:

     Install 118 Standard locations. Each location consisting of 4 Cat 5 4pr.
     PVC cables. All cables to terminate on modular patch panels in equipment
     room, and in 1 -- outlet box at the station location.

                      Material:            $19,056.60
                      Labor:               $15,611.40
                      Tax:                 $   952.83
                                           ----------
                      Total:               $35,620.83

Scope 2:

     Install I - 300Pr. Voice feel and 1 - 12 Strand multimode fiber from the
     main cross connect room (MC) to the intermediate cross connect room (ICC).

     The 300Pr. Voice feed to terminate 2 pairs each onto modular patch panels.





                                       43


<PAGE>   44
                                       MCC

                        Mahon Communications Corporation



     At the MC and ICC there will be, I - 24 Port Patch Panel to the 110 Voice
     wall field to cross connect outside service lines to equipment.

     A 12" Ladder tray will be installed above the 19" Equipment racks for cable
     access.

                      Material:            $ 7,898.85
                      Labor:               $ 4,233.60
                      Tax:                 $   394.95
                                           ----------
                      Total:               $12,527.40

Scope 3:

     Relocate Interspeeds Bay Networks high speed data network.

                      Labor Only:          $880.00

Scope 4:

     Relocate AT&T Merlin Telephone System.

                      Labor Only:          $960.00

All Scopes of work to be done on normal working hours Monday through Friday.

Summary:              Scope 1:      $35,056.60
                      Scope 2:      $12,527.40
                      Scope 3:      $   880.00
                      Scope 4:      $   960.00

               Total all above Scopes Off Work
                                    $49,424.00

Thank you for your interest in our company and its services.

Sincerely,



Steve Mahon, RCDD
Project Manager





                                       44


<PAGE>   45
                        Mahon Communications Corporation
                       803 Summer Street Boston, MA 02127
                      Main: 617-269-7100 Fax: 617-269-4306


Quote #               C-249
Company:              Interspeed
Contact:              Steve Ide
Project:              Stations Scope 1


Quotation:

 Qty       Part No.               Description
________________________________________________________________________________
 94000      004240500       Cat 5 4Pr. CMR
  236      OR-60950009      Dual Cat 5 RJ45 Jack
  118      OR-40300158      Faceplates
  119      OR-40300164      Blank Inserts
  118         2348          Work Boxes
  30          MPLS          Pre Wire Brackets
   4        55053-703       19" Equipment Racks
   2        11729-703       Double Vertical Section
  11      OR-851044791      48 Port Patch Panel
  22       OR-60400046      Cable Support Bar
  11      OR-808004410      Wire Manager
  118        KMPT-1         Station Labels
  472        KMPT-2         Patch Panel Labels
   4          MICK          Mounting Clamp Kit
  Lot       CAD Cat 5       Cat 5 Caddy Supports
  300       2300 BAC        Station Wire Mold
  140       PCCAT510        10' Statio Cat 5 Cords
  70         PCCAT55        5' Patch Cords Cat 5
  70         PCCAT57        7' Patch Cords Cat 5
  Lot       Cat 5 T&D       Cat 5 Test & Doc.
   1        As Built        As Built Drawing
  Lot        Permit         Wiring Permit
________________________________________________________________________________
                                             Sub-Total Material:    $19,056.60
          Installation, Staging, Testing and Project Management:    $15,611.40
                                                            Tax:    $   952.83
________________________________________________________________________________
                                              *TOTAL INVESTMENT:    $35,620.83



*Note: Investment does not include sales tax, shipping and handling.




                                       45


<PAGE>   46



Quote #                               C-249
Company:                              Interspeed
Contact:                              Steve Ide
Project:                              Feeds Scope 2


Quotation:

 Qty         Part No.                 Description
________________________________________________________________________________
  400         300240300         300 Pair Level 3 CMR
   8        OR-851044791        48 Port Patch Panel
  10        OR-808004410        Wire Manager
  18         OR-60400046        Cable Support Bar
  300         25240300          25Pr. Level 3 CMR
  2         OR-851044801        24 Port Patch Panels
  17         11OAW2-1 00        100 Pair Blocks
  50           11OC-4           Connecting Clips C-4
  10           11OC-5           Connecting Clips C-5
   2            188BI           Voice Managers
   8            150BI           Desi Strip Labels
  432          KMPT-l           Patch Panel Labels
   8          KMPT-110          Voice Labels
  400         12 MM CMR         12 Strand M/M Fiber CMR
  400       1" Inner CMR        1" Innerduct CMR
   2       OR-625MCC-12PR.      2 - 12 Port Rack Mt. LIU Loaded
  28        P202OC-C-125        ST/MM Fiber Connectors
   4           3MTSTST          Fiber Patch Cord M/M
   4          10250-012         12" Ladder Tray 10'
  Lot           L-Kit           Ladder Tray Install Kit
   8          11301-001         Butt-Splice Kit
   4         11421-1-12         Wall Angle Support
________________________________________________________________________________
                                             Sub-Total Material:    $ 7,898.85
          Installation, Staging, Testing and Project Management:    $ 4,233.60
                                                            Tax:    $   394.95
________________________________________________________________________________
                                              *TOTAL INVESTMENT:    $12,527.40

*Note: Investment does not include sales tax, shipping and handling.




                                       46


<PAGE>   47
                            SUBMISSION NOT AN OPTION



THE SUBMISSION OF THIS LEASE FOR EXAMINATION AND NEGOTIATION DOES NOT CONSTITUTE
AN OFFER TO LEASE, A RESERVATION OF, OR OPTION FOR THE PREMISES AND SHALL VEST
NO RIGHT IN ANY PARTY. TENANT OR ANYONE CLAIMING UNDER OR THROUGH TENANT SHALL
HAVE THE RIGHTS TO THE PREMISES AS SET FORTH HEREIN AND THIS LEASE SHALL BECOME
EFFECTIVE AS A LEASE ONLY UPON EXECUTION, ACKNOWLEDGMENT AND DELIVERY THEREOF BY
LANDLORD AND TENANT, REGARDLESS OF ANY WRITTEN OR VERBAL REPRESENTATION OF ANY
AGENT, MANAGER OR EMPLOYEE OF LANDLORD TO THE CONTRARY.

                    LANDLORD:  NAM Partners, L. P.

                    TENANT:    Brooktrout Technology, Inc., a
                               Massachusetts corporation

                    PREMISES:  Approximately 36,179 square feet located in
                               North Andover Mills, North Andover, Massachusetts










                                       47

<PAGE>   48
                                TABLE OF CONTENTS

                                                                           Page

ARTICLE I - BASIC LEASE PROVISIONS............................................1

ARTICLE II - PREMISES.........................................................2
         2.1      Premises....................................................2
         2.2      Common Areas................................................2
         2.3      Landlord's Reservations.....................................3
         2.4      Parking.....................................................3

ARTICLE III - TERM; LANDLORD'S AND TENANT'S WORK..............................3
         3.1      Term........................................................3
         3.2      Commencement Date...........................................4
         3.3      Extension Option............................................4
         3.5      Tenant's Work...............................................6

ARTICLE IV - RENT.............................................................7
         4.1      Base Rent and Additional Rent...............................7
         4.2      Security Deposit............................................7
         4.3      Additional Rent.............................................7

ARTICLE V - TENANT'S COVENANTS AND LANDLORD'S OBLIGATIONS
         ....................................................................10
         5.1      General Covenants..........................................10
         5.2      Environmental Covenants....................................11
         5.3      Landlord's Covenants.......................................12

ARTICLE VI - CONDITION OF PREMISES
         ....................................................................12
         6.1      Improvements...............................................12
         6.2      Fixtures: Yield-Up.........................................12
         6.3      Mechanic's Liens...........................................12

ARTICLE VII - INSURANCE
         ....................................................................13
         7.1      Insurance..................................................13
         7.2      Tenant's Risk..............................................13
         7.3      General Requirements.......................................13
         7.4      Indemnity..................................................14
         7.5      Waiver of Subrogation......................................14
         7.6      Landlord's Insurance.......................................14

ARTICLE VIII - CASUALTY AND EMINENT DOMAIN
         ....................................................................15
         8.1      Damage.....................................................15
         8.2      Termination Rights.........................................15
         8.3      Abatement..................................................15











                                       (i)


<PAGE>   49
         8.4      Taking for Temporary Use...................................15
         8.5      Disposition of Awards......................................15

ARTICLE IX - DEFAULTS AND REMEDIES...........................................16
         9.1      Tenant's Default...........................................16
         9.2      Damages....................................................16
         9.3      Landlord's Self-Help.......................................17
         9.4      Landlord's Default.........................................17

ARTICLE X - SUBORDINATION....................................................17
         10.1     Subordination..............................................17
         10.2     Request by Mortgagee.......................................17

ARTICLE XI - MISCELLANEOUS PROVISIONS........................................17
         11.1     Parties Bound..............................................17
         11.2     Landlord's Liabilities and Additional Rights...............18
         11.3     Holding Over...............................................18
         11.4     Quiet Environment..........................................18
         11.5     No Brokerage...............................................19
         11.6     Certificates...............................................19
         11.7     Notices....................................................19
         11.8     No Waiver..................................................19
         11.9     Force Majeure..............................................19
         11.10    Recording..................................................19
         11.11    Waiver of Jury Trial.......................................19
         11.12    Paragraph Headings.........................................19
         11.13    Governing Law..............................................20
         11.14    Severability: Construction and Interpretation..............20
         11.15    When Lease Becomes Binding; Entire Agreement...............20
         11.16    Assignment and Subletting..................................20
         11.17    Execution..................................................24





                                      (ii)