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                                                                    EXHIBIT 10.1




                    152 SECOND AVENUE, NEEDHAM, MASSACHUSETTS

                                      Lease

                                 by and between

                   Trustees of Needham 152 Second Avenue Trust

                                    LANDLORD

                                       and

                           Brooktrout Technology, Inc.

                                     TENANT

                            dated as of April 7, 1997


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                                TABLE OF CONTENTS

ARTICLE
NUMBER                               CAPTION                                PAGE
------                               -------                                ----

ARTICLE I

         RENT..................................................................2
         1.1...................................................................2
         1.2   Additional Rent - Operating Expenses............................3

ARTICLE II

         CONDITION OF PREMISES:

         DELIVERY OF PREMISES TO TENANT........................................4
         2.1...................................................................4
         2.2...................................................................4

ARTICLE III

         LANDLORD'S INTEREST AND ASSIGNMENT OF WARRANTIES......................4
         3.1...................................................................4
         3.2...................................................................4

ARTICLE IV

         TENANT'S COVENANTS....................................................4
         4.1...................................................................5
         4.2...................................................................5
         4.3...................................................................6
         4.4...................................................................6
         4.5...................................................................6
         4.6...................................................................6
         4.7...................................................................7

ARTICLE V

         MAINTENANCE AND REPAIRS...............................................7
         5.1...................................................................7
         5.2...................................................................7
         5.3...................................................................7

                                       (i)


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ARTICLE VI

         SERVICES............................................................. 8

ARTICLE VII

         IMPROVEMENTS......................................................... 8

ARTICLE VIII

         ALTERATIONS.......................................................... 9
         8.1   Non-structural Changes......................................... 9
         8.2   Structural Changes............................................. 9

ARTICLE IX

         INSPECTION...........................................................10

ARTICLE X

         FIRE, EMINENT DOMAIN, ETC............................................11
         10.1  Abatement of Rent..............................................11
         10.2  Landlord's Right of Termination................................11
         10.3  Restoration....................................................11
         10.4  Award..........................................................12

ARTICLE XI

         INSURANCE............................................................12
         11.1  ...............................................................12
         11.2  ...............................................................12
         11.3  ...............................................................13
         11.4  ...............................................................14

ARTICLE XII

         TAXES................................................................14
         12.1  ...............................................................14
         12.2  ...............................................................14
         12.3  ...............................................................14
         12.4  ...............................................................15
         12.5  ...............................................................15

                                      (ii)


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ARTICLE XIII

         SIGNS................................................................15

ARTICLE XIV

         DEFAULT..............................................................15
         14.1 ................................................................15
         14.2 ................................................................18

ARTICLE XV

         NOTICES..............................................................18

ARTICLE XVI

         ASSIGNMENT AND SUBLETTING............................................18
         16.1 ................................................................18
         16.2 ................................................................19

ARTICLE XVII

         MISCELLANEOUS PROVISIONS.............................................19
         17.1  Extra Hazardous Use............................................19
         17.2  Waiver.........................................................20
         17.3  Covenant of Quiet Enjoyment....................................20
         17.4  Landlord's Liability...........................................20
         17.5  Notice to Mortgagee or Ground Lessor...........................21
         17.6  Assignment of Rents and Transfer of Title......................21
         17.7  Tenant's Indemnity.............................................22
         17.8  Additional Charges.............................................22
         17.9  Invalidity of Particular Provisions............................22
         17.10 Provisions Binding, etc........................................22
         17.11 Recording......................................................23
         17.12 When Lease Becomes Binding.....................................23
         17.13 Paragraph Headings.............................................23
         17.14 Rights of Mortgagee or Ground Lessor...........................23
         17.15 Status Report..................................................23
         17.16 Remedying Defaults.............................................24
         17.17 Brokerage......................................................24
         17.18 First Option to Extend.........................................24
         17.19 Second Option to Extend........................................25
         17.20 Governing Law..................................................26

                                      (iii)


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                                      LEASE

PARTIES:

         THIS LEASE, made as of the 7th day of April, 1997, by and between
ARTHUR G. CARLSON, JR. and WILLIAM J. FORD, JR., as TRUSTEES OF NEEDHAM 152
SECOND AVENUE TRUST under Declaration of Trust dated October 30, 1972, and
registered with the Norfolk Registry District of the Land Court as Document No.
329795 on Certificate of Title No. 94585, having an office c/o William J. Ford,
Jr., 119 Maple Street, Sherbom, MA 01770 (hereinafter, the "Landlord") and
Brooktrout Technology, Inc., a ______ corporation having an office at 410 First
Avenue, Needham, MA 02194 (hereinafter, the "Tenant").

                                   WITNESSETH:

PREMISES:

         LANDLORD hereby leases to Tenant and Tenant hereby hires and takes from
Landlord all of the gross floor area in the building (the "Building") known and
numbered as 152 Second Avenue, Needham, Massachusetts (consisting of
approximately 30,888 rentable square feet, subject to verification as
hereinafter provided), and the land upon which the Building is located described
in Exhibit A annexed hereto, together with the appurtenances including but not
limited to all fixtures and equipment therein, including, without limitation,
all underground storage tanks, and all common walkways and driveways necessary
for access to the Building and the exclusive right to use the parking spaces
located in the open parking area adjacent to the Building, and any replacements
thereof (hereinafter, collectively, the "Premises"). The term "Lot" shall mean
all right, title and interest of the Landlord in and to the land described in
Exhibit A plus any additions or deletions thereto resulting from the involuntary
change of any abutting street line. The term "Property" shall mean the Building
and the Lot. At any time prior to the two (2) month anniversary of the
Commencement Date, Tenant may, at its sole cost and expense, have Tenant's
architect measure (utilizing the Boston BOMA standard method of measurement) and
confirm the actual rentable square footage of the Premises ("Premises Rentable
Area"). Tenant shall promptly provide Landlord with a copy of said architects
findings. If Landlord disputes such findings, Landlord shall, at its sole cost
and expense, have Landlord's architect measure (utilizing the Boston BOMA
standard method of measurement) and confirm the actual rentable square footage
of the Premises ("Premises Rentable Area"). If Landlord and Tenant are unable to
agree to the actual Premises Rentable Area, then the matter shall be submitted
to arbitration.

USE:

         To be used and occupied by Tenant for general office, research and
development, light manufacturing and warehouse uses, but excluding retail sales
(the "Permitted Uses"). It is specifically understood and agreed that Landlord
is making no representations or warranties




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that any or all of the Permitted Uses are allowable as of right under the
Needham Zoning By-Law, or that there are sufficient parking spaces on the Lot
for any or all of Tenant's Permitted Uses pursuant to said Zoning By-Law, or
that the Premises comply with any and all applicable laws, ordinances and
regulations. Tenant acknowledges that it has had an opportunity to examine the
relevant Needham Zoning By-Law and to make its own independent determination as
to the compliance of the Premises with applicable zoning requirements and such
compliance or non-compliance shall not be a condition precedent to Tenant's full
performance of its obligations under this Lease.

TERM:

         For a term (the "Term") of five (5) years, commencing on April 7, 1997
(the "Commencement Date") and expiring at the close of the day on April 6, 2002,
unless extended in accordance with Section 17.18, and if so extended then unless
further extended in accordance with Section 17.19 hereof.

         As used herein, the term "Lease Year' shall mean the period commencing
on the Commencement Date through and including the close of the day on the
twelve (I 2) month anniversary of the Commencement Date, and each successive
twelve (12) month period during the Term of this Lease.

         THIS LEASE is made upon the following additional terms and conditions,
which Landlord and Tenant covenant and agree to keep and perform:

                                    ARTICLE I

                                      RENT

         1.1 Tenant shall pay, promptly when due, without notice or demand, the
Annual Fixed Rent calculated as follows:

                Lease Year               Annual Fixed Rent
                ----------               -----------------

                     1                $7.00 per square foot of
                                      Premises Rentable Area

                     2-5              $7.50 per square foot of
                                      Premises Rentable Area.

         Annual Fixed Rent (sometimes hereinafter referred to as "Rent") shall
be paid in equal monthly installments of one-twelfth of such Annual Fixed Rent
in advance on the first day of each full calendar month during the Term, and the
corresponding fraction of said one-twelfth for any period of less than one month
at the beginning or end of the Term.

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         1.2      ADDITIONAL RENT - OPERATING EXPENSES

                  1.2.1 Tenant shall be responsible for contracting and paying
         for all services, including but not limited to utilities, necessary for
         the operation and maintenance and repair of the Property, and Tenant
         agrees to pay, or cause to be paid, all Operating Expenses for the
         Property. Operating Expenses for the Property shall include, without
         limitation, the following: (a) premiums for insurance carried with
         respect to the Property as set forth in Article M hereinbelow, (b)
         reasonable compensation and fringe benefits, workmen's compensation
         insurance premiums and payroll taxes paid to, or with respect to all
         persons actually engaged by Tenant in the operating, maintaining, or
         cleaning of the Building or Lot, (c) steam, water, sewer, electric,
         gas, oil, and telephone charges, (d) cost of building and cleaning
         supplies and equipment, (e) cost of all maintenance, cleaning and
         repairs, except as set forth in Articles V and X below, (f) cost of
         snow removal and care of landscaping, and (g) payments under service
         contracts with independent contractors, and all other ordinary and
         necessary expenses paid or incurred in connection with the operation,
         cleaning and maintenance of the Building and Lot.

                  1.2.2 If any Operating Expense for the Property shall not have
         been paid as required hereinabove, then Landlord, after ten (10) days
         written notice thereof to Tenant, may, but shall not be required to,
         pay the same, and shall thereupon become entitled to repayment of the
         substantiated amount thereof by Tenant as Additional Rent.
         Notwithstanding the foregoing, if during said ten (10) day notice
         period Tenant provides Landlord with written notice that it wishes to
         contest all or any part of such Operating Expense, Landlord shall not
         pay such Operating Expense while Tenant contests same, but only if such
         delay in payment will not affect Landlord's tide to the Property by the
         placement of liens thereon or otherwise.

                  1.2.3 Except as otherwise specifically provided herein, any
         sum, amount item or charge designated or considered as Additional Rent
         in this Lease shall be paid by Tenant to Landlord on the first day of
         the month following the date on which Landlord notifies Tenant in
         writing of the amount payable (or on the fifteenth day after the giving
         of such notice, whichever shall be later). Any such notice shall
         specify in reasonable detail the basis of such Additional Rent.

         1.3      Tenant will pay the Rent or Additional Rent due to Landlord,
or to such other person as Landlord may from time to time designate in writing.

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                                   ARTICLE II

                             CONDITION OF PREMISES:

                         DELIVERY OF PREMISES TO TENANT

         2.1 The Premises are being leased in their condition as of the
Commencement Date "as is", without representation or warranty of any kind.
Tenant specifically acknowledges that it has inspected the Building and Lot and
has found same, including without limitation all mechanical systems, roof,
structure, parking areas, and ceiling tiles, to be satisfactory to Tenant for
its purposes.

         2.2 If Landlord is prevented from delivering possession of the Premises
to Tenant on the Commencement Date because of delays caused by strikes, riots,
fire, acts of God, governmental intervention, refusal of current occupant to
vacate, acts or omissions of Tenant, or other causes which are not within the
reasonable control of Landlord (hereinafter, individually or collectively,
"Excusable Delay"), then the Commencement Date shall be extended by one day for
each day of an Excusable Delay. Notwithstanding the foregoing, in the event such
Excusable Delay shall exceed an aggregate of 75 days, Tenant may, at its option,
terminate this Lease by notice delivered to Landlord not later than twenty (20)
days after the aggregate 75-day period (such right of termination being Tenant's
sole and exclusive remedy at law or in equity against Landlord for Landlord's
failure to so deliver possession of the Premises).

                                   ARTICLE III

                LANDLORD'S INTEREST AND ASSIGNMENT OF WARRANTIES

         3.1 Landlord represents that it holds its interest in the Premises
pursuant to a duly registered deed, and that it has the right to make this Lease
for the Term aforesaid; that the provisions of this Lease do not conflict with
or violate the provisions of existing agreements between Landlord and third
parties.

         3.2 Landlord shall assign to Tenant the benefit of any vendor's or
contractors warranties received by Landlord on the Building or any component
thereof or equipment located or installed therein.

                                   ARTICLE IV

                               TENANT'S COVENANTS

         Tenant covenants during the Term and such further time as Tenant
occupies any part of the Premises:

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         4.1      to pay when due all Annual Fixed Rent and Additional Rent and
all other amounts due hereunder;

         4.2      (a)      except as otherwise provided in Section 4.2(b) and in
Articles V and X hereof, at Tenant's sole cost and expense to keep the Premises,
including without limitation all underground storage tanks, if any, walks,
drives, exterior walls, mechanical systems and parking area, in good order,
repair and condition, reasonable wear and tear, damage by fire and other insured
casualty and eminent domain only excepted, and all glass windows (except glass
in exterior walls unless the damage thereto is attributable to Tenant's
negligence or misuse) and doors of the Premises whole and in good condition with
glass of the same quality as that injured or broken, damage by fire and other
insured casualty and eminent domain only excepted, and at the expiration or
termination of this Lease peaceably to yield up the Premises and all alterations
and additions thereto in good order, repair and condition, reasonable wear and
tear, damage by fire, insured casualty and eminent domain only excepted, first
removing all goods and effects of tenant and, to the extent specified by
Landlord by notice to Tenant at the time it consents to the installation of
same, all alterations and additions made by Tenant or on behalf of Tenant and
all partitions, and repairing any damage caused by such removal and restoring
the Premises and leaving them clean and neat. If, based upon Tenant's use of the
Premises or upon any incident occurring on or about the Property during the Term
of this Lease, Landlord reasonably believes that the Property may have been
contaminated, then upon Landlord's written request Tenant will furnish to
Landlord, not later than the Termination of this Lease, a report, prepared at
Tenant's expense by an engineering firm qualified to make reports under
Massachusetts General Laws Chapter 21E and reasonably acceptable to Landlord,
stating that the Building and Lot have been examined for oil and hazardous waste
contamination and that no such contamination was found on the Building or Lot
(or that such contamination was found, but cleaned up and disposed of by Tenant
and that the Building and Lot are now free of such substances). Notwithstanding
the foregoing, if Tenant can demonstrate by clear and convincing evidence
(including for example the chemical nature, off-Premises geographical source,
the third-party responsible for, and approximate time of the subject discharges)
that any such contamination or identifiable portion thereof was caused by a
third party for whose conduct Tenant is not legally responsible, Tenant shall
not be liable to Landlord for cleanup or removal or remediation of such
contamination or identifiable portion thereof, as the case may be. If requested
by Landlord, Tenant shall, at its cost, provide Landlord with an analysis by an
environmental engineering from qualified pursuant to Massachusetts General Laws
Chapter 21E to support any conclusion of non-liability advanced by Tenant.

                  (b)      Tenant shall, not later than June 15, 1997, furnish
to Landlord a report, prepared at Tenant's expense by an engineering firm
qualified to make reports under Massachusetts General Laws Chapter 21E and
reasonably acceptable to Landlord, stating that environmental testing has been
performed in the vicinity of the existing underground storage tank on the Lot.
Tenant shall indemnify and hold Landlord harmless from any and all damage, cost
and expense incurred by Landlord as a result of the performance of such
environmental testing. If the report indicates that oil and/or hazardous waste
contamination was found on the

                                        5


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Lot, and any remediation of same is required by applicable laws, Landlord shall
indemnify and hold Tenant harmless from the costs and expenses of remediating
such contamination whether performed by the Landlord or any third party.
Notwithstanding the foregoing, if Landlord can demonstrate by clear and
convincing evidence that any such contamination or identifiable portion thereof
was caused by Tenant or a third party for whose conduct Tenant is legally
responsible, Tenant shall be liable to Landlord for cleanup or removal or
remediation of such contamination or identifiable portion thereof, as the case
may be.

         4.3      continuously from the Commencement Date to use and occupy the
Premises for the Permitted Uses, and not to injure or deface the Premises,
Building or Lot, nor permit in the Premises and inflammable fluids or chemicals
(except in accordance with law and with prior written notice to Landlord of
Tenant's intention to use same), or nuisance, or the emission from the Premises
of any objectionable noise or odor, nor use or devote the Premises or any part
thereof for any purpose other than the Permitted Uses, nor any use thereof which
is inconsistent with the maintenance of the Building as an office building of
the first class in the quality of its maintenance, use and occupancy, or which
is improper, offensive, contrary to law or ordinance or which would invalidate
or increase the premiums for any insurance on the Building or its contents or
which would render necessary any alteration or addition to the Building.
Notwithstanding the foregoing, Tenant may vacate all or any part of the Premises
during the Term, provided that (i) Tenant provides Landlord with reasonable
prior written notice, (ii) Tenant continues to pay Rent and all other charges
for the remainder of the Term, and (iii) Tenant takes all measures necessary to
keep the Building secure; 4.4 to comply with all reasonable rules and
regulations now or hereafter made by Landlord of which Tenant has been given
advance written notice, for the care and use of the Building and Lot and their
facilities and approaches;

         4.4      in its use of the Premises, to comply with the requirements of
all applicable governmental laws, rules and regulations and to keep the Premises
equipped with all safety appliances required by law or ordinance or any other
regulation of any public authority, and to procure all required licenses and
permits and to comply with such licenses and permits. Without limiting the
generality of the foregoing, Tenant shall be responsible, in connection with
Tenant's use of the Premises, for compliance with the Americans with
Disabilities Act of 1990 (42 U.S.C. ss.12101 ET SEQ.) and the regulations and
Accessibility Guidelines for Buildings and Facilities issued pursuant thereto
(collectively, the "ADA Requirements");

         4.5      not to place a load upon the Premises exceeding an average
rate of 75 pounds of live load per square foot of floor area (partitions shall
be considered as part of the live load); and not to move any safe, vault or
other heavy equipment in, about or out of the Premises except in such manner and
at such time as Landlord shall in each instance authorize, such authorization
not to be unreasonably withheld or delayed;

         4.6      to pay promptly when due all taxes which may be imposed upon
personal property (including, without limitation, fixtures and equipment) in the
Premises to whomever assessed; and,

                                        6


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         4.7      to vacate the Premises upon the end of the Term should Tenant
hold over after the termination of this Lease, by lapse of time or otherwise,
Tenant shall become a daily tenant at sufferance at a rate equal to the then
fair market rental rate of the Premises but in no event less than 1 1/2 times
the Annual Fixed Rent in effect on the expiration or termination date. Tenant
shall also pay Landlord all direct and foreseeable damages (including any loss
of a tenant or rental income), sustained by reason of any such holding over.
Otherwise, such holding over shall be on the terms and conditions set forth in
this Lease as far as applicable.

                                    ARTICLE V

                             MAINTENANCE AND REPAIRS

         5.1      During the Term of this Lease Tenant shall take reasonable
care of the Premises and Landlord's fixtures and appurtenances therein and
thereon and shall perform all maintenance and make all repairs and replacements
to the Premises not specifically imposed upon Landlord by the express provisions
hereof. All repairs and replacements made by Tenant shall be equal in quality to
that in place on the Commencement Date. Notwithstanding the foregoing, with
respect to the three (3) 200 ton chillers located on the roof of the Building,
and any other mechanical system serving the Premises, Tenant shall repair same
and keep same in good working order throughout the Term of this Lease. Should
any of such chillers or other mechanical system or component thereof require
replacement during the Term of this Lease, Tenant may replace same with a
chiller or mechanical system or component thereof, as the case may be, of size,
capacity, function and quality customarily found in buildings the size and type
of the Building in the Route 128 area, which shall provide the Building with
adequate heat, air conditioning and ventilation (or other mechanical service, as
the case may be) for the Permitted Uses.

         5.2      Landlord's obligations under this Article shall consist of
making all structural repairs, replacements and alterations (but excluding
general maintenance and repairs of a non-structural nature) to the exterior and
bearing walls of the Building and support beams, and columns and lateral support
thereto, and to perform all repairs and restoration required by Article X.
Landlord's obligations do not include, without limitation. repairs to or
maintenance or replacement of plumbing or sewer lines, underground storage
tanks, or the repair or replacement of the roof membrane and deck, the HVAC
systems or the primary distribution electrical service equipment, all of which
shall be Tenant's responsibility at Tenant's expense during the Tenant of this
Lease or any extension thereof.

         5.3      Landlord reserves the right to stop any service or utility
system, when necessary by reason of accident or emergency, or until necessary
repairs which Landlord is obligated to perform pursuant to the Terms of this
Lease have been completed, but only to the extent that such stoppage is
reasonably necessary under the circumstances; provided, however, that in each
instance of stoppage, Landlord shall exercise reasonable diligence to eliminate
the cause thereof. Except in case of emergency repairs, Landlord will give
Tenant reasonable advance

                                        7


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notice of any contemplated stoppage and will use reasonable efforts to avoid
unnecessary inconvenience to Tenant by reason thereof.

         Landlord shall not be liable to Tenant for any compensation or
reduction of rent by reason of inconvenience or annoyance or for loss of
business arising from the necessity of Landlord or its agents entering the
Premises for any of the purposes in this Lease authorized, or for repairing the
Premises or any portion of the Building however the necessity may occur. In case
Landlord is prevented or delayed from making any repairs, alterations or
improvements, or furnishing any services or performing any other covenant or
duty to be performed on Landlord's part, by reason of any cause reasonably
beyond Landlord's control, Landlord shall not be liable to Tenant therefor, nor,
except as expressly otherwise provided in Section 10.1, shall Tenant be entitled
to any abatement or reduction of rent by reason thereof, nor shall the same give
rise to a claim in Tenant's favor that such failure constitutes actual or
constructive, total or partial, eviction from the Premises.

                                   ARTICLE VI

                                    SERVICES

         Landlord shall not be required to furnish any services or utilities to
the Premises during the Term of this Lease, the Tenant hereby assuming full and
sole responsibility for the supply of and payment for such services and
utilities.

                                   ARTICLE VII

                                  IMPROVEMENTS

         Subject to compliance with Articles IV and VM hereof, Tenant may place
partitions, trade or other fixtures (including lighting fixtures), personal
property, machinery, equipment and the like in the Premises (collectively,
hereinafter "FF&E') and may make such improvements and alterations therein and
thereon as it may desire at its own expense. All such things heretofore or
hereafter made or installed by or for Tenant and paid for by Tenant shall remain
the property of Tenant and in case of damage or destruction thereto by fire or
other causes, Tenant shall have the right to recover the value thereof as its
own loss from any insurance company with which it has insured the same,
notwithstanding that any of such things might be considered a part of the
Premises. At the expiration or earlier termination of the Term, Tenant shall
remove all of FF&E and, to the extent specified by Landlord at the time it
consents to the installation of same, all alterations and additions made by
Tenant and all partitions, and shall repair any damage to the Premises caused by
such removal. Any of such things which remain in the Premises after the
expiration or termination of this Lease shall be deemed conclusively to have
been abandoned, and either may be retained by Landlord as its property or may be
disposed of in such manner as Landlord may see fit, at Tenant's sole cost and
expense. Notwithstanding the foregoing, Tenant shall not be required to remove
pipes,

                                        8


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wires and the like from walls, ceilings or floors, provided Tenant properly
cuts, disconnects and caps such pipes and wires and seals them off, if
necessary, in a safe and lawful manner.

                                  ARTICLE VIII

                                   ALTERATIONS

         8.1      NON-STRUCTURAL CHANGES. Tenant shall have the right, upon
prior written notice to Landlord, at Tenants sole cost and expense, to make
non-structural changes, alterations, additions, or improvements to or upon the
Premises which do not interfere with any heating, air-conditioning, electrical
or plumbing systems or structural element or the exterior of the Building,
provided Landlord is furnished copies of all working drawings prepared in
connection with such changes at least ten (10) days prior to the commencement of
such work (except as to changes which involve primarily the movement of unfixed
partitions, the configuration of Tenant space, painting, flooring, relocation of
doors, and replacement of hung ceiling panels, in which event Landlord need not
be furnished with copies of working drawings). Non-structural changes,
alterations, additions and improvements shall include, without limitation, the
installation, removal or relocation of light fixtures, trade fixtures and
partitions that are not bearing walls. If any such non-structural changes,
alterations, additions or improvements are not readily adaptable to normal
office and/or engineering and research and development uses at reasonable
expense, Landlord may, by notice delivered within ten (10) days of Landlord's
receipt of plans with respect thereto (or if no plans are required, within ten
(10) days of Landlord's receipt of prior written notice of the installation
thereof), require Tenant, upon expiration of the Lease, to restore those
portions of the Premises containing such modifications to the condition existing
prior to the making of such modifications.

         8.2      STRUCTURAL CHANGES. Tenant shall have the right, at Tenant's
sole cost and expense, to make structural changes, alterations, additions or
improvements to or upon the Premises, provided that Tenant obtains the prior
written consent of Landlord, which consent shall not be unreasonably withheld or
delayed. Landlord shall not be deemed unreasonable for withholding approval of
any alterations or additions which (a) affects or might affect any structural or
exterior element of the Building, or (b) will require unusual expense to
re-adapt the Premises to normal office and/or engineering and research and
development uses upon termination of the Lease or increase the cost of insurance
or taxes on the Building unless Tenant first gives assurance acceptable to
Landlord for payment of such increased cost and that such re-adaptation will be
made prior to such termination without expense to Landlord.

                  8.2.1 At least thirty (30) days prior to commencing such work,
         Tenant shall furnish Landlord with copies of the plans and
         specifications for such work. Landlord agrees to review such plans and
         specifications promptly upon receipt thereof, and to notify Tenant of
         its approval or any comments within (30) days of such receipt.

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                  8.2.2 As a condition of its consent, and simultaneously with
         the grant thereof, Landlord may, in its reasonable discretion: (i)
         require Tenant, at Tenant's sole cost and expense, to perform certain
         additional work if such work is necessary to correct impairments to the
         structure of the Building or to mechanical systems which would be
         caused by the proposed changes; and/or (ii) notify Tenant that Landlord
         will require Tenant, upon expiration of the Lease, to restore portions
         or all of the Premises to the condition existing prior to the making of
         such modifications if (but only if) such structural changes,
         alterations, additions or improvements are unusual in nature or not
         readily adaptable to normal engineering and research and development
         uses at a reasonable expense.

         8.3      With respect to all work by Tenant pursuant to Section 8.1 or
8.2 hereof, Tenant shall secure all licenses and permits necessary therefor,
and, if requested by. Landlord, deliver to Landlord a statement of the names of
all Tenant's contractors and subcontractors and the estimated cost of all labor
and material to be furnished by them. In the course of such work, Tenant agrees
(i) to use labor compatible with that being employed by Landlord for work in or
to the Building, and not to employ or permit the use of any labor or otherwise
take any action which might result in a labor dispute involving personnel
providing services in the Building. Tenant's contractors shall (i) carry general
liability insurance with limits of at lease $1,000,000/$3,000,000, and property
damage insurance with limits of at least $1,000,000 (all insurance to be written
in companies reasonably approved by Landlord and insuring Landlord and Tenant as
well as the contractors), and deliver to Landlord certificates of all such
insurance, and (ii) in the event that the cost of such work exceeds $250,000.00,
have filed with Landlord lien bonds and the like in form acceptable to Landlord.

         8.4      Tenant agrees to pay promptly when due the entire cost of work
to be done on the Premises by Tenant, its agents, employees, or independent
contractors, and not to cause or permit any liens for labor or materials
performed or furnished in connection therewith to attach to the Premises and
immediately to discharge any such liens which may so attach.

         8.5      All construction work required or permitted by this Lease
shall be done in a good and workmanlike manner and in compliance with all
applicable laws and ordinances, regulations and orders of governmental authority
and insurers of the Building, and shall be coordinated with any work being
performed by Landlord.

                                   ARTICLE IX

                                   INSPECTION

         The Landlord shall, upon at least twenty-four (24) hours prior verbal
notice (except in the case of emergency) to Tenant's designated representative,
have the right at all reasonable times during business hours to inspect the
Premises and show the same to prospective mortgagees, purchasers and/or tenants,
and at all times to make repairs or replacements as

                                       10


<PAGE>   15



required by this Lease or as may be necessary, provided, however, that Landlord
shall use all reasonable efforts not to disturb Tenant's use and occupancy of
the Premises.

                                    ARTICLE X

                           FIRE, EMINENT DOMAIN, ETC.

         10.1 ABATEMENT OF RENT. If the Premises shall be damaged by fire or
casualty, Annual Fixed Rent and other charges payable by Tenant shall abate
proportionately for the period in which, by reason of such damage, there is
substantial interference with Tenant's use of the Premises, having regard to the
extent to which Tenant may be required to discontinue Tenant's use of all or a
portion of the Premises, but such abatement or reduction shall end upon the date
on which Landlord shall have substantially restored the Premises (excluding any
alterations, additions or improvements made by Tenant) to the condition in which
they were prior to such damage. If the Premises or access thereto shall be
affected by any exercise of the power of eminent domain, Annual Fixed Rent and
other charges payable by Tenant shall be jointly and equitably abated and
reduced according to the nature and extent of the loss of use thereof suffered
by Tenant. In no event shall Landlord have any liability for damages to Tenant
for inconvenience, annoyance, or interruption of business arising from such
fire, casualty or eminent domain.

         10.2 LANDLORD'S RIGHT OF TERMINATION. If the Premises are substantially
damaged by fire or casualty (the term "substantially damaged" meaning damage of
such a character that the same cannot, in ordinary course, reasonably be
expected to be repaired within two-hundred seventy (270) days from the time the
repair work would commence), or if there is insufficient insurance proceeds
available to restore the Premises and the loss is not covered by insurance
referred to in Section 11.1 hereinbelow, or if any material part of the Building
is taken by any exercise of the right of eminent domain, then Landlord shall
have the right to terminate this Lease (even if Landlord's entire interest in
the Premises may have been divested) by giving notice of Landlord's election so
to do within 90 days after the occurrence of such casualty or the effective date
of such Notice, whereupon this Lease shall terminate thirty (30) days after the
date of such notice with the same force and effect as if such date were the date
originally established as the expiration date hereof.

         10.3 RESTORATION. If the Premises shall be damaged by fire or casualty
which is covered by the insurance referred to in Section 11.1 hereinbelow, or a
portion thereof taken by the exercise of the right of eminent domain and if this
Lease shall not be terminated pursuant to Section 10.2, Landlord shall
thereafter use due diligence to restore the Premises (excluding any alterations,
additions or improvements made by Tenant) to proper condition for Tenant's use
and occupation, provided that Landlord's obligation shall be limited to the
amount of insurance proceeds or eminent domain award available therefor. If, for
any reason, such restoration shall not be substantially completed within six
months after the expiration of the 90-day period referred to in Section 10.2
(which six-month period may be extended for such periods of time as Landlord is
prevented from proceeding with or completing such restoration for any cause

                                       11


<PAGE>   16



beyond Landlord's reasonable control), Tenant shall have the right to terminate
this Lease by giving notice to Landlord thereof within thirty (30) days after
the expiration of such period (as so extended). Upon the giving of such notice,
this Lease shall cease and come to an end without further liability or
obligation on the part of either party unless, within such 30-day period,
Landlord substantially completes such restoration. Such right of termination
shall be Tenant's sole and exclusive remedy at law or in equity for Landlord's
failure so to complete such restoration.

         10.4 AWARD. Landlord shall have and hereby reserves and excepts, and
Tenant hereby grants and assigns to Landlord, all rights to recover for damages
to the Property and leasehold interest hereby created, and to compensation
accrued or hereafter to accrue by reason of such taking, damage or destruction,
and by way of confirming the foregoing, Tenant hereby grants and assigns, and
covenants with Landlord to grant and assign to Landlord, all rights to such
damages or compensation. Nothing contained herein shall be construed to prevent
Tenant from prosecuting in any condemnation proceedings a claim for the value of
any of Tenant's removable property, leasehold improvements or FF&E installed in
the Premises by Tenant at Tenant's expense and for relocation expenses, provided
that such action shall not affect the amount of compensation otherwise
recover-able by Landlord from the taking authority.

                                   ARTICLE XI

                                    INSURANCE

         11.1 Tenant shall, from and after the Commencement Date hereof,
maintain insurance covering the Building against loss, damage or destruction
caused by boiler explosion, fire and the perils specified in the standard
extended coverage endorsement, and by vandalism and malicious mischief, and by
earthquake and flood, and for other risks customarily insured against by owners
of similar buildings in the vicinity of the Building. Coverage shall equal one
hundred percent (100%) of the replacement cost of the Building. Tenant shall
also maintain (i) liability insurance in the amount of at least
$1,000,000/$3,000,000, (ii) property damage insurance in the amount of at least
$3,000,000, or such greater amounts as Landlord shall from time to time
reasonably request, and (iii) rent loss insurance covering at least twelve (12)
months of rent. All such policies shall be in form and substance reasonably
acceptable to Landlord and shall name Landlord (and those in privity of estate
with Landlord), Landlord's mortgagee and Tenant as a loss payee, and shall bear
the endorsement that such policies shall not be cancelled until after thirty
(30) days written notice to Landlord. Tenant shall deposit promptly with
Landlord certificates evidencing such coverage. In the event of any casualty or
other insured damage to the Building, all insurance proceeds shall be made
available for the restoration of the Building, and any mortgage covering the
Building shall so provide, subject, however, to the terms and conditions of such
mortgage which govern the application and disbursement of insurance proceeds for
restoration.

         11.2 Notwithstanding anything else to the contrary in this Lease
contained, the parties hereto agree that neither party, nor its agents,
employees, contractors or invitees, shall

                                       12


<PAGE>   17



be liable to the other for loss or damage caused by any risk covered by any of
the insurance coverages herein described, and in implementation hereof, the
parties hereby agree as follows:

                           (a) If Landlord shall suffer any loss, damage,
                  liability or expense for which Tenant shall be obligated to
                  pay Landlord, Tenant shall have as an offset against said
                  obligation the greater of (i) the net proceeds of any
                  insurance that Landlord receives with respect to such loss,
                  damage, liability or expense or (ii) the amount of insurance
                  coverage Landlord has agreed to obtain, regardless of whether
                  Landlord actually has obtained it, if such loss, damage,
                  liability or expense shall have resulted from a risk or peril
                  required hereunder to have been covered by such insurance.

                           (b) If Tenant shall suffer any loss, damage,
                  liability or expense for which Landlord shall be obligated to
                  pay Tenant, Landlord shall have as an offset against said
                  obligation the greater of (i) the net proceeds of any
                  insurance that Tenant receives with respect to such loss,
                  damage, liability or expense or (ii) the amount of insurance
                  coverage Tenant has agreed to obtain, regardless of whether
                  Tenant actually has obtained it, if such loss, damage,
                  liability or expense shall have resulted from a risk or peril
                  required hereunder to have been covered by such insurance.

                           (c) Notwithstanding the foregoing with respect to the
                  offset in the amount of insurance proceeds received, the
                  parties acknowledge that such offset shall not cause the
                  insurer which has paid the proceeds to declare the governing
                  policy invalid. The parties therefore mutually agree that each
                  shall obtain a rider to, endorsement on, or clause in, any
                  insurance policy covering the Premises and the Building and
                  personal property, fixtures and equipment located therein by
                  which their insurers shall waive subrogation. By virtue of
                  such rider, endorsement, or clause, the parties hereby agree
                  that they will not make any claim against or seek to recover
                  from each other for any loss or damage to their own property
                  or to the property of others by reason of a risk or peril
                  covered by such insurance.

         11.3     Tenant agrees and acknowledges that all of the furnishings,
fixtures, equipment, effects and property of every kind, nature and description
of Tenant and of all persons claiming by, through or under Tenant which, during
the continuance of this Lease or any occupancy of the Premises by Tenant or
anyone claiming under Tenant, may be on the Premises or elsewhere in the
Building or on the Lot, shall be at the sole risk and hazard of Tenant, and if
the whole or any part thereof shall be destroyed or damaged by fire, water or
otherwise, or by the leakage or bursting of water pipes, steam pipes, or other
pipes, by theft or from any other cause, no part of said loss or damage is to be
charged to or be borne by Landlord.

                                       13


<PAGE>   18



         11.4     Tenant hereby covenants that in the event of any loss, damage
or destruction of the Building and improvements on the Premises which Landlord
is required by the operation of Article X to repair and restore, the proceeds
which are payable under policies of insurance carried by Tenant, together with
the amount of any deductible limits established by Tenant, shall upon request of
Landlord, first be paid over to Landlord to repair and reconstruct the Building
and improvements on the Premises to the extent required by this Lease, before
such proceeds are applied in any other manner including, without limitation, the
satisfaction of Tenant's debts secured by a mortgage or other lien instrument,
or interest thereon.

                                   ARTICLE XII

                                      TAXES

         12.1     (a)      For the purposes of this Article, the term "Tax Year"
shall mean the twelve-month period commencing on the July 1 immediately pending
the Commencement Date and each twelve-month period thereafter commencing during
the Term of this Lease. The term "Taxes" shall mean real estate taxes and other
taxes, levies and assessments imposed upon the Property; charges, fees,
assessments and payments for transit, housing, police, fire or other
governmental services or purported benefits to the Property; and service or user
payments in lieu of taxes. Betterment assessments and interest thereon shall be
apportioned equally over the longest period permitted by law. Taxes for the
years in which this Lease commences and terminates shall be prorated.

                  (b)      Tenant shall pay all Taxes assessed on the Property
during the Term of this Lease on or before the date upon which they are due to
be paid without interest. Promptly after receipt by Landlord of bills for such
Taxes, Landlord shall advise Tenant of the amount thereof (and shall provide
Tenant with a copy of same) and the computation of Tenant's payment on account
thereof Landlord shall have the same rights and remedies for the non-payment by
Tenant of any payments due on account of Taxes as Landlord has hereunder for the
failure of Tenant to pay Annual Fixed Rent.

         12.2     (a)      If some method or type of taxation shall replace the
current method of assessment of real estate taxes in whole or in part, or the
type thereof, or if additional types of taxes are imposed upon the Property or
Landlord relating to the Property, Tenant agrees that Tenant shall pay the same
as an additional charge.

                  (b)      If a tax (other than Federal or State income tax) is
assessed on account of the rents or other charges payable by Tenant to Landlord
under this Lease, Tenant agrees to pay the same as an additional charge within
ten (10) days after billing therefor, unless applicable law prohibits the
payment of such tax by Tenant.

         12.3     Tenant shall have the right, by appropriate proceedings, to
protest or contest any assessment or re-assessment for Taxes, or any special
assessment, or the validity of either, or of any change in assessments or the
tax rate.

                                       14


<PAGE>   19



         12.4     In any such contest or proceedings, Tenant may act in its own
name and/or the name of Landlord and Landlord will, at Tenant's request,
cooperate with Tenant in any way Tenant may reasonably require in connection
with such contest or proceedings. Landlord shall sign such consents or other
documents as Tenant may reasonably request. Any contest or proceedings conducted
by Tenant shall be at Tenant's expense and, in the event any penalties, interest
or late charges become payable with respect to the Taxes as a result of such
contest, Tenant shall pay the same. Landlord shall be solely responsible for the
payment of any penalties, interest or late charges which are imposed through no
fault of Tenant.

         12.5     Tenant shall be entitled to receive any tax refunds properly
allocable to the Term of this Lease, as it may be extended, and relating to
Taxes paid by Tenant, as a result of any such contests or proceedings.

                                  ARTICLE XIII

                                      SIGNS

         Tenant shall have the exclusive right to place its signs anywhere in,
on and about the Building, the Lot and land, provided the same are in compliance
with all applicable laws and ordinances, are in good taste and in keeping with a
quality industrial park, are first approved by Landlord which approval shall not
be unreasonably withheld or delayed, are purchased and installed at the sole
cost and expense of Tenant and are removed from the Premises at the expiration
or earlier termination of the Term hereof.

                                   ARTICLE XIV

                                     DEFAULT

         14.1     (a)      If at any time subsequent to the date of this Lease
any one or more of the following events (herein referred to as a "Default of
Tenant') shall happen:

                           (i)      Tenant shall fail to pay the Annual Fixed
                  Rent or other charges hereunder when due and such failure
                  shall continue for five (5) full business days after Tenant's
                  receipt of written notice; or

                           (ii)     Tenant shall neglect or fail to perform or
                  observe any other covenant herein contained on Tenant's part
                  to be performed or observed, and Tenant shall fail to remedy
                  the same within thirty (30) days after written notice to
                  Tenant specifying such neglect or failure, or if such failure
                  is of such a nature that Tenant cannot reasonably remedy the
                  same within such thirty (30) day period, Tenant shall fail to
                  commence promptly to remedy the same and to prosecute such
                  remedy to completion with diligence and continuity; or

                                       15


<PAGE>   20



                           (iii)    Tenant's leasehold interest in the Premises
                  shall be taken on execution or by other process of law
                  directed against Tenant; or

                           (iv)     Tenant shall make an assignment for the
                  benefit of creditors or shall file a voluntary petition in
                  bankruptcy or shall be adjudicated bankrupt or insolvent, or
                  shall file any petition or answer seeking any reorganization,
                  arrangement, composition, readjustment, liquidation,
                  dissolution or similar relief for itself under any present or
                  future Federal, State or other statute, law or regulation for
                  the relief of debtors, or shall seek or consent to or
                  acquiesce in the appointment of any trustee, receiver or
                  liquidator of Tenant or of all or any substantial part of its
                  properties, or shall admit in writing its inability to pay its
                  debts generally as they become due; or

                           (v)      A petition shall be filed against Tenant in
                  bankruptcy or under any other law seeking any reorganization,
                  arrangement, composition, readjustment, liquidation,
                  dissolution, or similar relief under any present or future
                  Federal, State or other statute, law or regulation and shall
                  remain undismissed or unstayed for an aggregate of sixty (60)
                  days (whether or not consecutive), or if any debtor in
                  possession (whether or not Tenant) trustee, receiver or
                  liquidator of Tenant or of all or any substantial part of its
                  properties or of the Premises shall be appointed without the
                  consent or acquiescence of Tenant and such appointment shall
                  remain unvacated or unstayed for an aggregate of sixty (60)
                  days (whether or not consecutive);

         then in any such case (1) if such Default of Tenant shall occur prior
to the Commencement Date, this Lease shall IPSO FACTO, and without further act
on the part of Landlord, terminate, and (2) if such Default of Tenant shall
occur after the Commencement Date, Landlord may terminate this Lease by notice
to Tenant, and thereupon this Lease shall come to an end as fully and completely
as if such date were the date herein originally fixed for the expiration of the
Term of this Lease, and Tenant will then quit and surrender the Premises to
Landlord, but Tenant shall remain liable as hereinafter provided.

                  (b)      If this Lease shall be terminated as provided in this
Article, or if any execution or attachment shall be issued against Tenant or any
of Tenant's property whereupon the Premises shall be taken or occupied by
someone other than Tenant, then Landlord may, without notice, re-enter the
Premises, either by summary proceedings, ejectment or otherwise, and remove and
dispossess Tenant and all other persons and any and all property from the same,
as if this Lease had not been made, and Tenant hereby waives the service of
notice of intention to reenter or to institute legal proceedings to that end.

                  (c)      In the event of any termination, Tenant shall pay the
Annual Rent and other sums payable hereunder up to the time of such termination,
and thereafter Tenant, until the end of what would have been the Term of this
Lease in the absence of such termination, and whether or not the Premises shall
have been relet, shall be liable to Landlord for, and shall

                                       16


<PAGE>   21



pay to Landlord, as liquidated current damages, the Annual Fixed Rent and other
sums which would be payable hereunder if such termination had not occurred, less
the net proceeds, if any, of any reletting of the Premises, after deducting all
reasonable expenses in connection with such reletting, including, without
limitation, all repossession costs, brokerage commissions, legal expenses,
attorneys' fees, advertising, expenses of employees, alteration costs and
expenses of preparation for such reletting. Tenant shall pay such current
damages to Landlord monthly on the days which the Annual Rent would have been
payable hereunder if this Lease had not been terminated.

                  (d)      At any time after such termination, whether or not
Landlord shall have collected any such current damages: as liquidated final
damages and in lieu of all such current damages beyond the date of such demand,
at Landlord's election Tenant shall pay to Landlord an amount equal to the
aggregate of the Annual Fixed Rent and other charges accrued under the Lease in
the twelve (12) months ended next prior to such termination (or such shorter
period of time as would have remained in the Term but for such termination) plus
the amount of Annual Fixed Rent and other charges of any kind accrued and unpaid
at the time of termination.

                  (e)      In the case of any Default of Tenant, re-entry,
expiration and dispossession by summary proceeding or otherwise, Landlord may
(i) re-let the Premises or any part or parts thereof, either in the name of
Landlord or otherwise, for a term or terms which may at Landlord's option be
equal to or less than or exceed the period which would otherwise have
constituted the balance of the Term of this Lease and may grant reasonable
concessions or free rent-to the extent that Landlord considers advisable and
necessary to re-let the same and (ii) may make such alterations, repairs and
decorations in the Premises as Landlord in its sole judgment considers advisable
and necessary for the purpose of re-letting the Premises; and the making of such
alterations, repairs and decorations shall not operate or be construed to
release Tenant from liability hereunder as aforesaid. Landlord shall in no event
be liable in any way whatsoever for failures to re-let the Premises provided
that Landlord agrees to use commercially reasonable efforts to re-let the
Premises, or, in the event that the Premises are re-let, for inability
reasonably to collect the rent under such re-letting. Tenant hereby expressly
waives any and all rights of redemption granted by or under any present or
future laws in the event of Tenant being evicted or dispossessed, or in the
event of Landlord obtaining possession of the Premises, by reason of the
violation by Tenant of any of the covenants and conditions of this Lease.

                  (f)      The specified remedies to which Landlord may resort
hereunder are not intended to be exclusive of any remedies or means of redress
to which Landlord may at any time be entitled to lawfully, and Landlord may
invoke any remedy (including the remedy of specific performance) allowed at law
or in equity as if specific remedies were not herein provided for.

                                       17


<PAGE>   22



                  (g)      All reasonable costs and expenses incurred by or on
behalf of Landlord (including, without limitation, attorneys' fees and expenses)
in enforcing its rights hereunder or occasioned by any Default of Tenant shall
be paid by Tenant.

         14.2     Landlord shall in no event be in default of the performance of
any of Landlord's obligations hereunder unless and until Landlord shall have
failed to perform such obligations within thirty (30) days, or such additional
time as is reasonably required to correct any such default, after notice by
Tenant to Landlord specifying wherein Landlord has failed to perform any such
obligations.

                                   ARTICLE XV

                                     NOTICES

         Whenever, by the terms of this Lease, notices, consents or approvals
shall or may be given either to Landlord or to Tenant such notices, consents or
approvals shall be in writing and shall be sent by registered or certified mail,
postage prepaid, or by a recognized national courier service ("Courier"):

         If intended for Landlord, addressed to Landlord at Landlord's address
         first set forth above (or to such other address as may from time to
         time hereafter by designated by Landlord by like notice), with a copy
         to William S. Abbott, Esq., 50 Congress Street, Suite 925, Boston, MA
         02109.

         If intended for Tenant, addressed to Tenant at Tenant's address first
         set forth above until the Commencement Date and thereafter to the
         Premises (or to such other address or addresses as may from time to
         time hereafter be designated by Tenant by like notice), Attention:
         Robert Leahy, CFO, with a copy to Paul L. Baccari, Esq., Masterman,
         Culbert & Tully, One Lewis Wharf, Boston, MA 02110.

All such notices shall be effective when deposited in the United States Mail
within the Continental United States, or the next day if sent by Courier,
provided that the same are received in ordinary course at the address to which
the same were sent.

                                   ARTICLE XVI

                            ASSIGNMENT AND SUBLETTING

         16.1     Tenant may assign this Lease or sublet the Premises or any
portion thereof only with the prior written consent of Landlord, which consent
may be withheld at Landlord's sole discretion except as hereinafter expressly
otherwise provided. Landlord agrees not to withhold its consent to any
subletting of all or any portion of the Premises, provided Tenant requests same
in writing ("Tenant's Request"), and provided (i) at the time thereof Tenant is
not in default under this Lease beyond any applicable cure period; (ii)
Landlord, in its discretion

                                       18


<PAGE>   23



reasonably exercised, determines that the proposed sublessee is not financially
irresponsible, and that the reputation, business, proposed use of the Premises
by the proposed sublessee are satisfactory to Landlord; (iii) any sublessee
shall expressly assume all obligations of this Lease on Tenant's part to be
performed; (iv) such consent, if given, shall not release Tenant of any of its
obligations under this Lease (including, without limitation, its obligation to
pay rent) and Tenant's liability after any subletting shall be joint and several
with the sublessee; (v) Tenant shall reimburse Landlord promptly for reasonable
legal and other expenses incurred by Landlord in connection with Tenant's
Request; (vi) Tenant agrees specifically to pay over to Landlord, as additional
rent, fifty percent (50%) of all sums provided to be paid under the terms and
conditions of such sublease which are in excess of the amounts otherwise
required to be paid pursuant to this Lease; and (vii) a consent to one
subletting to any other person shall not be deemed to be a consent to any
subsequent subletting. Any assignment subletting or occupancy without Landlord's
prior consent shall be void and shall, at the option of Landlord, constitute a
default under this therein shall be assignable as to the interest of Tenant by
operation of law without the prior written consent of Landlord, which consent
may be arbitrarily withheld. Tenant agrees that in the event that Landlord
withholds its consent to Tenant's Request contrary to the provisions of this
paragraph, Tenant's sole remedy shall be to seek an injunction in equity to
compel performance by Landlord to give its consent to Tenant's Request, and
Tenant expressly waives any right to damages in the event of such withholding of
consent by Landlord to Tenant's Request.

         16.2     The provisions of Section 16.1 shall apply to a transfer (by
one or more transfers) of a majority of the stock or partnership interests, or
other evidences of ownership of Tenant as if such transfer were an assignment of
this Lease; but such provisions shall not apply to transactions with an entity
into or with which Tenant is merged or consolidated or to which substantially
all of Tenant's assets are transferred or to any entity which controls or is
controlled by Tenant or is under common control with Tenant, provided that in
any of such events (i) the successor to Tenant has a net worth computed in
accordance with generally accepted accounting principles at least equal to the
net worth of Tenant immediately prior to such merger, consolidation or transfer,
(ii) proof satisfactory to Landlord of such net worth shall have been delivered
to Landlord at least 10 days prior to the effective date of any such reaction,
and (iii) the assignee agrees directly with Landlord, by written instrument in
form satisfactory to Landlord, to be bound by all the obligations of Tenant
hereunder including, without limitation, the covenant against further assignment
or subletting; and provided further that this Section 16.2 shall not apply to
the transfer of stock of Tenant so long as the stock of Tenant is publicly
traded on a nationally recognized stock exchange.

                                  ARTICLE XVII

                            MISCELLANEOUS PROVISIONS

         17.1     EXTRA HAZARDOUS USE. Tenant covenants and agrees that Tenant
will not do or permit anything to be done in or upon the Premises, or bring in
anything keep anything therein, which shall increase the rate of property or
liability insurance on the Premises or of

                                       19


<PAGE>   24



the Building above the standard rate applicable to premises being occupied for
Permitted Uses unless Tenant notifies Landlord in advance of such event and then
promptly pays to Landlord, on demand, any such increase resulting therefrom
which shall be due and payable as an additional charge hereunder, or provides to
Landlord insurance certificates indicating coverage for same at Tenant's sole
expense protecting Landlord and Tenant.

         17.2     WAIVER. (a) Failure on the part of Landlord or Tenant to
complain of any action or non-action on the part of the other, no matter how
long the same may continue, shall never be a waiver by Tenant or Landlord,
respectively, of any of the other's rights hereunder. Further, no waiver at any
time of any of the provisions hereof by Landlord or Tenant shall be construed as
a waiver of any of the other provisions hereof, and a waiver at any time of any
of the provisions hereof shall not be construed as a waiver at any subsequent
time of the same provisions. The consent or approval of Landlord or Tenant to or
of any action by the other requiring such consent or approval shall not be
construed to waive or render unnecessary Landlord's or Tenant's consent or
approval to or of any subsequent similar act by the other.

                  (b) No payment by Tenant, or acceptance by Landlord, of a
lesser amount than shall be due from Tenant to Landlord shall be treated
otherwise than as a payment on account of the earliest installment of any
payment due from Tenant under the provisions hereof. The acceptance by Landlord
of a check for a lesser amount with an endorsement or statement thereon, or upon
any letter accompanying such check, that such lesser amount is payment in full,
shall be given no effect, and Landlord may accept such check without prejudice
to any other rights or remedies which Landlord may have against Tenant.

         17.3     COVENANT OF QUIET ENJOYMENT. Tenant, subject to the terms and
provisions of this Lease, on payment of the Annual Fixed Rent and all other
charges and observing, keeping and performing all of the other terms and
provisions of this Lease on Tenant's part to be observed, kept and performed,
shall lawfully, peaceably and quietly have, hold, occupy and enjoy the Premises
during the term hereof, without hindrance or ejection by any persons lawfully
claiming under Landlord to have title to the Premises superior to Tenant; the
foregoing covenant of quiet enjoyment is in lieu of any other covenant, express
or implied.

         17.4     LANDLORD'S LIABILITY. (a) Tenant specifically agrees to look
solely to Landlord's then equity interest in the Property at the time owned, for
recovery of any judgment from Landlord; it being specifically agreed that
Landlord (original or successor) shall never be personally liable for any such
judgment, or for the payment of any monetary obligation to Tenant. The provision
contained in the foregoing sentence is not intended to, and shall not, limit any
right that Tenant might otherwise have to obtain injunctive relief against
Landlord or Landlord's successors in interest, or to take any action not
involving the personal liability of Landlord (original or successor) to respond
in monetary damages from Landlord's assets other than Landlord's equity interest
in the Property.

                  (b) With respect to any services to be furnished by Landlord
to Tenant, Landlord shall in no event be liable for failure to furnish the same
when prevented from doing

                                       20


<PAGE>   25



so by strike, lockout, breakdown, accident, order or regulation of or by any
governmental authority, or failure of supply, or inability by the exercise of
reasonable diligence to obtain supplies, parts or employees necessary to furnish
such services, or because of war or other emergency, or for any cause beyond
Landlord's reasonable control, or for any cause due to any act or neglect of
Tenant or Tenant's servants,, agents, employees, licensees or any person
claiming by, through or under Tenant.

                  (c) In no event shall Landlord ever be liable to Tenant for
any indirect or consequential damages suffered by Tenant from whatever cause.

                  (d) With respect to any repairs or restoration which are
required or permitted to be made by landlord, the same may be made during normal
business hours and Landlord shall have no liability for damages to Tenant for
inconvenience, annoyance or interruption of business arising therefrom; provided
that Landlord agrees to use reasonable efforts to minimize interference with
Tenant's business.

         17.5     NOTICE TO MORTGAGEE OR GROUND LESSOR. After receiving notice
from any person, firm or other entity that it holds a mortgage or a ground lease
which includes the Premises, no notice from Tenant to Landlord alleging any
default by Landlord shall be effective unless and until a copy of the same is
given to such holder or ground lessor (provided Tenant shall have been furnished
with the name and address of such holder or ground lessor), and the curing of
any of Landlord's defaults by such holder or ground lessor shall be treated as
performance by Landlord.

         17.6     ASSIGNMENT OF RENTS AND TRANSFER OF TITLE. (a) With reference
to any assignment by Landlord of Landlord's interest in this Lease, or the rents
payable hereunder, conditional in nature or otherwise, which assignment is made
to the holder of a mortgage on property which includes the Premises, Tenant
agrees that the execution thereof by Landlord, and the acceptance thereof by the
holder of such mortgage, shall never be treated as an assumption by such holder
of any of the obligations of Landlord hereunder unless such holder shall, by
notice sent to Tenant, specifically otherwise elect and that, except as
aforesaid, such holder shall be treated as having assumed Landlord's obligations
hereunder only upon foreclosure of such holder's mortgage and the taking of
possession of the Premises.

                  (b) In no event shall the acquisition of Landlord's interest
in the Property by a purchaser which, simultaneously therewith, leases
Landlord's entire interest in the Property back to the seller thereof be treated
as an assumption by operation of law or otherwise, of Landlord's obligations
hereunder, but Tenant shall look solely to such seller-lessee, and its
successors from time to time in title, for performance of Landlord's obligations
hereunder. In any such event, this Lease shall be subject and subordinate to the
lease to such purchaser. For all purposes, such seller-lessee, and its
successors in title, shall be the Landlord hereunder unless and until Landlord's
position shall have been assumed by such purchaser lessor. In the event of a
sale or leaseback, the purchaser and the fee holder shall provide to Tenant a
non-disturbance and attornment agreement whereby such purchaser and fee holder,
as the case

                                       21


<PAGE>   26



may be, agrees to recognize the Lease (and Tenant agrees to attorn in such
event) in the event that the seller/lessee defaults.

                  (c) Except as provided in paragraph (b) of this Section, in
the event of any transfer of title to the Property by Landlord, Landlord shall
thereafter be entirely freed and relieved from the performance and observance of
all covenants and obligations hereunder arising after the date of such transfer.

         17.7     TENANT'S INDEMNITY. To the maximum extent this agreement may
be made effective according to law, Tenant agrees to defend, indemnify and save
harmless Landlord from and against all claims, loss, liability, costs and
damages of whatever nature arising from any default by Tenant under this Lease
or from the following: (i) from any accident, injury or damage whatsoever to any
person, or to the property of any person, occurring in or about the Building or
Lot (except those due to Landlord's negligence or willful misconduct); or (ii)
in connection with the conduct or management of the Premises or of any business
therein, or any thing or work whatsoever done, or any condition created (other
than by Landlord) in or about the Premises; and, in any case, occurring after
the date of this Lease, until the end of the Term of this Lease, and thereafter
so long as Tenant is in occupancy of the Premises. This indemnity and hold
harmless agreement shall include indemnity against all reasonable costs,
expenses and liabilities incurred in, or in connection with, any such claim or
proceeding brought thereon, and the defense thereof, including, without
limitation, reasonable attorneys' fees and costs at both the trial and appellate
levels.

         17.8     ADDITIONAL CHARGES. If Tenant shall fail to pay when due any
sums under this Lease as an additional charge, Landlord shall have the same
rights and remedies as Landlord has hereunder for failure to pay Annual Fixed
Rent.

         17.9     INVALIDITY OF PARTICULAR PROVISIONS. If any term or provision
of this Lease, or the application thereof to any person or circumstance shall,
to any extent, be invalid or unenforceable, the remainder of this Lease, or the
application of such term or provision to persons or circumstances other than
those as to which it is held invalid or unenforceable, shall not be affected
thereby, and each term and provision of this Lease shall be valid and be
enforced to the fullest extent permitted by Law.

         17.10    PROVISIONS BINDING, ETC. Except as herein otherwise provided,
the terms hereof shall be binding upon and shall inure to the benefit of the
successors and assigns, respectively, of Landlord and Tenant and, if Tenant
shall be an individual, upon and to his heirs, executors, administrators,
successors and assigns. Each term and each provision of this Lease to be
performed by Tenant or Landlord shall be construed to be both a covenant and a
condition. The reference contained to successors and assigns of Tenant is not
intended to constitute a consent to assignment by Tenant, but has reference only
to those instances in which Landlord may later give consent to a particular
assignment as provided elsewhere in this Lease.

                                       22


<PAGE>   27



         17.11    RECORDING. Tenant agrees not to record this Lease, but each
party hereto agrees, on the request of the other, to execute a so-called notice
of lease in form recordable and complying with applicable law and reasonably
satisfactory to Landlord's attorneys. In no event shall such document set forth
the rent or other charges payable by Tenant under this Lease; and any such
document shall expressly state that it is executed pursuant to the provisions
contained in Lease, and is not intended to vary the terms and conditions of this
Lease.

         17.12    WHEN LEASE BECOMES BINDING. 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 hereof by both
Landlord and Tenant. All negotiations, considerations, representations and
understandings between Landlord and Tenant are incorporated herein and this
Lease expressly supersedes any proposals or other written documents relating
hereto. This Lease may be modified or altered only by written agreement between
Landlord and Tenant and no act or omission of any employee or agent of Landlord
shall alter, change or modify any of the provisions hereof.

         17.13    PARAGRAPH HEADINGS. The paragraph headings throughout this
instrument are for convenience and reference only, and the words contained
therein shall in no way be held to explain, modify, amplify or aid in the
interpretation, construction, or meaning of the provisions of this Lease.

         17.14    RIGHTS OF MORTGAGEE OR GROUND LESSOR. This Lease shall be
subordinate to any mortgage or ground lease from time to time encumbering the
Premises, whether executed and delivered prior to or subsequent to the date of
this Lease, if the holder of such mortgage or ground lease shall so elect
provided that the holder of such mortgage or ground lease shall provide Tenant
with a subordination, non-disturbance and attornment agreement (the "Agreement")
in form and substance reasonably acceptable to Tenant (it being agreed that the
form and substance of the Subordination, Non-Disturbance and Attornment
Agreement attached hereto as Exhibit ND is reasonably acceptable to Tenant). If
this Lease is subordinate to any mortgage or ground lease and the holder thereof
(or successor) shall succeed to the interest of Landlord, Tenant shall attorn to
such holder (or successor) and this Lease shall continue in full force and
effect between such holder (or successor) and Tenant in accordance with the
terms of the Agreement. Tenant agrees to execute such Agreement in confirmation
of the foregoing provisions as such holder may request, and Tenant hereby
appoints such holder (or successor) as Tenant's attorney-in-fact to execute such
Agreement upon default of Tenant in complying with such holder's (or
successor's) request.

         17.15    STATUS REPORT. Recognizing that both parties may find it
necessary to establish to third parties, such as accountants, banks, mortgagees,
ground lessors, or the like, the then current status of performance hereunder,
either party, on the request of the other made from time to time, will promptly
furnish to the Landlord, or the holder of any mortgage or ground lease
encumbering the Premises, or to Tenant, as the case may be, a statement of the
status of

                                       23


<PAGE>   28



any matter pertaining to this Lease, including, without limitation,
acknowledgment that (or the extent to which) each party is in compliance with
its obligations under the terms of this Lease.

         17.16    REMEDYING DEFAULTS. Landlord shall have the right, but shall
not be required, to pay such sums or to do any act which requires the
expenditure of monies which may be necessary or appropriate by reason of the
failure or neglect of Tenant to perform any of the provisions of this Lease, and
in the event of the exercise of such right by Landlord, Tenant agrees to pay to
Landlord forthwith upon demand all such sums, together with interest thereon at
a rate equal to 4% over the prime rate in effect from time to time at the First
National Bank of Boston as an additional charge. Any payment of Annual Fixed
Rent or other sums payable hereunder not paid when due shall, at the option of
Landlord, bear interest at a rate equal to 4% over the prime rate in effect from
time to time at the First National Bank of Boston from the due date thereof and
shall be payable forthwith on demand by Landlord, as an additional charge.

         17.17    BROKERAGE. Tenant warrants and represents that Tenant has
dealt with no broker in connection with the consummation of this Lease other
than Lynch, Murphy, Walsh & Partners Incorporated (the "Broker") and, in the
event of any brokerage claims against Landlord predicated upon prior dealings
with Tenant, Tenant agrees to defend the same and indemnify Landlord against any
such claim (except any claim by the Broker). Landlord shall hold Tenant harmless
with respect to any brokerage commissions due to the Broker in connection with
the consummation of this transaction, except to the extent that Tenant has
breached the foregoing warranty.

         17.18    FIRST OPTION TO EXTEND. Tenant shall have the option to extend
the initial Term as to the entire Premises for one (1) period of four (4) years
(the "First Extension Period"), upon the same terms and conditions then in
effect with respect to the Premises, except for Annual Fixed Rent, which shall
be determined as provided hereinbelow, provided that at the time such option to
extend is exercised and at the expiration of the initial Term Tenant shall not
be in default under this Lease beyond any applicable cure period.

         The Annual Rent for the First Extension Period payable with respect to
the Premises shall be the greater of (i) 90% of the prevailing fair market
rental rate for the Premises as of the date of commencement of the First
Extension Period, as determined as hereinafter set forth, or (ii) the Annual
Fixed Rent payable by Tenant with respect to the Premises for the last Lease
Year during the initial Term.

         At any time after November 15, 2000 and prior to February 1, 2001,
Tenant may request Landlord to inform Tenant of the prevailing fair market
rental rate for the Premises which will be in effect for the First Extension
Period, and in such event Landlord shall within thirty (30) days thereafter
notify Tenant as to the prevailing fair market rental rate for the First
Extension Period as of the commencement of the First Extension Period, as
determined by Landlord.

                                       24


<PAGE>   29



         If Tenant elects to exercise the First Option to Extend, Tenant shall
do so by written notice to Landlord ("Tenant's Exercise") given not later than
March 14, 2001. If Tenant fails to exercise the First Option to Extend within
the aforesaid time period, Tenant's right to any extension of the Term of this
shall expire. Tenant's Exercise shall contain a statement from Tenant that it
either accepts or rejects Landlord's determination of the prevailing fair market
rental rate for the Premises. If Tenant rejects Landlord's determination of the
prevailing fair market rental rate for the Premises. then Tenant's Exercise
shall also contain the name of one qualified appraiser. In such event Landlord
shall, within thirty (30) days of Landlord's receipt of Tenant's Exercise,
provide Tenant with written notice of a second qualified appraiser, and these
two qualified appraisers shall name a third. It shall then be the duty of the
appraisers to ascertain the prevailing fair market rental rate for the Premises,
and if any appraiser shall neglect or refuse to appear at any meeting appointed
by the appraisers, a majority may act in the absence of such appraiser. An
appraisers' determination of the prevailing fair market rental rate for the
Premises shall be conclusive and shall be binding upon Landlord and Tenant.
Landlord and Tenant shall each be responsible for the costs of their respective
appraiser, and Landlord and Tenant shall each be responsible for fifty percent
(50%) of the costs of the third appraiser. An appraiser hereunder shall be
deemed qualified if a member in good standing of the American Institute of Real
Estate Appraisers or a comparable recognized professional organization and such
appraiser has at least five years experience in providing fair market rental
value appraisals of commercial real estate in Route 128 area. The third
appraiser that is selected by the two appraisers that are appointed by Landlord
and Tenant respectively must not have undertaken appraisal or other such work on
behalf of either party or any affiliates of either party during the firm year
period before such third appraiser's selection.

         17.19    SECOND OPTION TO EXTEND. Tenant shall have the option to
further extend the Term as to the entire Premises for one (1) period of five (5)
years (the "Second Extension Period"), upon the same terms and conditions then
in effect with respect to the Premises, except for Annual Fixed Rent, which
shall be determined as provided hereinbelow, provided that (i) Tenant has
exercised its First Option to Extend in a. timely manner in accordance with
Section 17.18, and (ii) at the time such option to extend is exercised and at
the expiration of the First Extension Period Tenant shall not be in default
under this Lease beyond any applicable cure period.

         The Annual Rent for the Second Extension Period payable with respect to
the Premises shall be the greater of (i) 90% of the prevailing fair market
rental rate for the Premises as of the date of commencement of the Second
Extension Period, as determined as hereinafter set forth, or (ii) the Annual
Fixed Rent payable by Tenant with respect to the Premises for the last Lease
Year during the First Extension Period.

         At any time after November 15, 2004 and prior to February 1, 2005,
Tenant may request Landlord to inform Tenant of the prevailing fair market
rental rate for the Premises which will be in effect for the Second Extension
Period, and in such event Landlord shall within thirty (30) days thereafter
notify Tenant as to the prevailing fair market rental rate for

                                       25


<PAGE>   30



the Second Extension Period as of the commencement of the Second Extension
Period, as determined by Landlord.

         If Tenant elects to exercise the Second Option to Extend, Tenant shall
do so by written notice to Landlord ("Tenant's Exercise") given not later than
March 14, 2005. If Tenant fails to exercise the Second Option to Extend within
the aforesaid time period, Tenant's right to any extension of the Tenant of this
Lease shall expire. Tenant's Exercise shall contain a statement from Tenant that
it either accepts or rejects Landlord's determination of the prevailing fair
market rental rate for the Premises. If Tenant rejects Landlord's determination
of the prevailing fair market rental rate for the Premises, then Tenant's
Exercise shall also contain the name of one qualified appraiser. In such event
Landlord shall, within thirty (30) days of Landlord's receipt of Tenant's
Exercise, provide Tenant with written notice of a second qualified appraiser,
and these two qualified appraisers shall name a third. It shall then be the duty
of the appraisers to ascertain the prevailing fair market rental rate for the
Premises, and if any appraiser shall neglect or refuse to appear at any meeting
appointed by the appraisers, a majority may act in the absence of such
appraiser. The appraisers' determination of the prevailing fair market rental
rate for the Premises shall be conclusive and shall be binding upon Landlord and
Tenant Landlord and Tenant shall each be responsible for the costs of their
respective appraiser, and Landlord and Tenant shall each be responsible for
fifty percent (50%) of the costs of the third appraiser. An appraiser hereunder
shall be deemed qualified if a member in good standing of the American Institute
of Real Estate Appraisers or a comparable recognized professional organization
and such appraiser has at least five years experience in providing fair market
rental value appraisals of commercial real estate in Route 128 area. The third
appraiser that is selected by the two appraisers that are appointed by Landlord
and Tenant respectively must not have undertaken appraisal or other such work on
behalf of either party or any affiliates of either party during the three year
period before such third appraisers selection.

         17.20    GOVERNING LAW. This Lease shall be governed exclusively by the
provisions hereof and by the laws of the Commonwealth of Massachusetts, as the
same may from time to time exist.

                                       26


<PAGE>   31



         IN WITNESS WHEREOF, Landlord and Tenant have caused this Lease to be
duly executed, under seal, by persons hereunto duly authorized, in multiple
copies, each to be considered an original hereof, as of the date first set forth
above.

NEEDHAM 152 SECOND AVENUE TRUST


By:
    ------------------------------------------
    Arthur G. Carlson, Jr., as Trustee but
    not individually



By:
    ------------------------------------------
    William J. Ford, Jr., as Trustee but not
    individually


TENANT:

BROOKTROUT TECHNOLOGY, INC.


By:
    ------------------------------------------
    Hereunto duly authorized

Title:


                                       27


<PAGE>   32



                                    Exhibit A

                             Description of Premises

         The following described real property, together with the buildings and
improvements constructed thereon, situated on Second Avenue in the New England
Industrial Center, in Needham, County of Norfolk, Massachusetts, bounded and
described as follows:

PARCEL I (Registered Land):

SOUTHWESTERLY              by Second Avenue, two hundred twenty six and 56/100
                           (226.56) feet;

NORTHWESTERLY              by lot numbered 29, as indicated on plan hereinafter
                           referred to, two hundred thirty nine and 80/100
                           (239.80) feet;

NORTHEASTERLY              by lands now or formerly of Christopher Kalinowski et
                           al and of John Mroczka et al, one hundred forty six
                           and 51/100 (146.51) feet;

NORTHERLY                  by land now or formerly of said John Mroczka et al,
                           eighty six and 31/100 (86.31) feet;

SOUTHEASTERLY              one hundred eight and 89/100 (108.89) feet;

NORTHEASTERLY              seventy seven and 03/100 (77.03) feet, by land now or
                           formerly of Chester Mickowski;

SOUTHEASTERLY              by lot numbered 36, as shown on said plan, one
                           hundred sixty eight and 02/100 (168.02) feet; and

SOUTHERLY                  by land now or formerly of Orono Corporation, one
                           hundred eighteen and 97/100 (118.97) feet.

         Said parcel is shown as lot numbered 37 on a plan drawn by William S.
Crocker Inc., Civil Engineer, dated April 22, 1957, as approved by the Land
Court, filed in the Land Registration Office as No. 24606H, a copy of a portion
of which is filed in Norfolk Registry District with Certificate No. 59771, Sheet
1, Book 299.

         So much of the above described land as is included within the limits of
said Second Avenue is subject to such highway easements as were taken therein by
the Town of Needham under instrument dated April 13, 1954 and duly recorded in
Book 3253, Page 315; to such easement for sewer, water and drainage purposes as
set forth in a grant made by Gerald W. Blakeley, Jr., et al, Trustees to the
Town of Needham, dated May 18, 1954, duly recorded in




<PAGE>   33



Book 3263, Page 57; and to such private rights and easements as may exist in,
under or over the same at date of original decree.

         So much of the above described land as is included within the area
marked "The New York, New Haven and Hartford Railroad Company Easement" on said
plan is subject to rights and easements as set forth in a grant made by Gerald
W. Blakeley, Jr., et al, Trustees to the New York, New Haven and Hartford
Railroad Company, dated March 26, 1954, duly recorded in Book 3252., Page 421.

         The above described land is subject to rights and easements as set
forth in a grant made by Gerald W. Blakeley, Jr., et al, Trustees to the
Company and New England Telephone and Telegraph Company, dated March 12, 1954,
duly recorded in Book 3248, Page 3.

The above described land is subject also to and has the benefit of the rights,
restrictions etc., as set forth or referred to in Document No. 194917.

PARCEL 2 (Recorded Title not registered)

SOUTHWESTERLY              by Second Avenue, 16 feet;

NORTHWESTERLY              28 feet on a line in said Second Avenue and by a
                           curved line by said lot 37,79.21 feet;

SOUTHWESTERLY              77.27 feet and 28 feet on a line in said Second
                           Avenue by land now or formerly of Orono Corporation;

         Or however otherwise said premises may be bounded and described and be
all or any of said measurements and contents more or less.

         Said parcel is shown as Lot I on said Plan 24606H, filed in the
Engineer's Office of the Land Court and contains 774 square feet to side line of
Second Avenue according thereto. Title to said parcel is not registered. This
Parcel is Parcel 2 described in three deeds, one to each of the Grantor Trusts
which are the Landlord's predecessors in title, and recorded with the Norfolk
Registry of Deeds in Book, 3598, Page 417-419. These Premises are subject to and
with the benefit of rights, covenants and restrictions referred to therein.

         Parcels 1 and 2 are also subject to a mortgage to the Provident
Institution for Savings in the Town of Boston, Registered as Document No.
329796, and recorded in Book 4892, Page 181.

                                        2


<PAGE>   34



                                   EXHIBIT ND

             SUBORDINATION, NONDISTURBANCE AND ATTORNMENT AGREEMENT

         THIS SUBORDINATION, NONDISTURBANCE AND ATTORNMENT AGREEMENT, dated as
of                 , is made among                       , a corporation with
a principal place of business at                 , (hereinafter, the "Tenant"),
                     , having an address                       , (hereinafter,
collectively the "Borrower"), and                        having a usual place
of business at                  (hereinafter, the "Bank"), the Mortgagee under
a certain Mortgage and Security Agreement granted by the Borrower to the Bank
dated on the date hereof and filed for registration herewith (hereinafter, the
"MORTGAGE".

                                   WITNESSETH:

         WHEREAS, the Borrower is the owner of real property with buildings and
improvements thereon located at         , Needham, Massachusetts (hereinafter,
the "Premises") as further described in Certificate of Title No. filed with the
Norfolk District Land Registry Office (hereinafter, the "Registry"); and

         WHEREAS, the Tenant and the Borrower have entered into a certain Lease
Agreement dated June 18, 1996 (hereinafter, said Lease Agreement shall be
referred to as the "LEASE") with respect to the Premises, Notice of which Lease
is filed herewith; and

         WHEREAS, the Borrower has entered into a loan arrangement with the Bank
pursuant to which the Borrower has granted the Mortgage to the Bank and
collaterally assigned the Borrower's interest in the Lease to the Bank, as
provided in the Collateral Assignment of Leases and Rents dated on the date
hereof filed for registration herewith (the "Collateral Assignment"); and

         WHEREAS, the Bank has indicated that the Bank requires as a condition
to the establishment of such loan arrangement an agreement with the Tenant as to
the priority of the Lease and the relative rights of the Bank and Tenant
thereto,

         NOW THEREFORE, in consideration of the foregoing and the mutual
covenants hereinafter contained, the Tenant, the Borrower, and the Bank hereby
agree as follows:

         1.       REPRESENTATIONS BY TENANT AND BORROWER. The Tenant and the
Borrower hereby represent and warrant the following to be true as of the date
hereof.

                  (a) That the Lease is a complete statement of the agreement
         between the parties thereto with respect to the letting of the
         Premises;




<PAGE>   35



                  (b) That the Lease is currently in full force and in effect
         according to its terms and is a binding obligation of the Tenant and
         the Borrower as of the date hereof; and

                  (c) That the Tenant is not now in default (beyond applicable
         notice and cure periods) under any term or terms of the Lease and that,
         to the best of the Tenant's present knowledge, there is no default or
         claim of default on the pail of, or claim of offset against the rent or
         any other sum or sums payable under the terms of the Lease to, the
         Borrower under the Lease.

                  (d) That the Tenant has not made any assignment for the
         benefit of creditors nor filed any petitions or instituted any
         proceedings under the bankruptcy or similar laws of the United States
         or of any state, and that there are currently no such petitions or
         proceedings pending or threatened against the Tenant.

         2.       CONSENT TO ASSIGNMENT BY TENANT. The Tenant hereby consents to
the assignment of the Lease and the rents thereunder to the Bank pursuant to the
Mortgage and the Collateral Assignment. Upon notification by the Bank to the
Tenant of the exercise of the Bank's rights under the Mortgage and/or the
Collateral Assignment, the Tenant shall pay rent and any other sums payable
under the terms of the Lease directly to the Bank. Without limiting the
foregoing, the Tenant hereby acknowledges and agrees that the Bank shall have no
duties or obligations with respect to the Lease until the Bank has notified the
Tenant of the Bank's assumption of the Borrower's obligations under the Lease,
or until the Bank has made entry under or foreclosed upon the Mortgage or has
taken actual possession of the Premises and Landlord shall hold Tenant harmless
from following such directions by Bank to Tenant.

         3.       COVENANTS. Regardless of whether or not the Bank has notified
the Tenant of the exercise by the Bank of its rights under the Mortgage and/or
the Collateral Assignment, the -Tenant hereby agrees as follows:

                  (a) Except as otherwise provided in the Lease, not to cancel
         terminate, surrender, amend or modify the Lease or any term thereof,
         nor consent to or accept any such cancellation, termination, surrender,
         amendment or modification thereof, nor permit any event reasonably
         within the Tenant's control which would operate to terminate,
         surrender, or cancel the Lease provided that Tenant is so obligated
         under the terms of the Lease;

                  (b) Except as otherwise provided in the Lease, or as
         previously approved by Landlord, not, without prior written consent of
         the Bank, to make or cause to be made, any structural additions,
         alterations, or improvements, to the Premises.

         4.       BANK'S OPPORTUNITY TO CURE DEFAULT. Regardless of whether the
Bank has notified the Tenant of the Bank's exercise of its rights under the
Mortgage and/or the Collateral Assignment, the Tenant shall notify the Bank of
any default on the part of the

                                        2


<PAGE>   36



Borrower under the Lease. Except as otherwise provided in the Lease, no such
default shall entitle or allow the Tenant to cancel or terminate the Lease, or
abate the rent or any other sums owing thereunder, or exercise any other remedy
afforded by the Lease or applicable law, unless the Bank fails to cure or cause
to be cured, the specified default within 30 days of receipt of such notice, or
within such longer time as may be required for cure due to the nature of such
default, provided the cure is commenced within said 30-day period and thereafter
diligently prosecuted to completion, and provided that said notice is duly
given.

         5.       SUBORDINATION OF LEASE. The Tenant hereby agrees and
acknowledges that the Lease and any extensions of said Lease or its terms shall
be subordinate and subject to the lien of the Mortgage and any renewals,
extensions, modifications or replacements thereof as though the Mortgage and any
such renewal, extension, modification, or replacement thereof had been executed,
acknowledge and delivered prior to the Lease and recorded prior to the Lease or
any notice of the Lease.

         6.       ATTORNMENT BY TENANT. The Tenant further attorn to the Bank
and agrees that, in the event of the exercise by the Bank of its rights under
the Mortgage, and the taking of possession or the acquisition of tide by the
Bank, pursuant to the Mortgage, whether through foreclosure proceedings or
otherwise, the Tenant shall recognize the Bank and its successors, whether
through foreclosure sale or otherwise, as the landlord under the Lease and the
Lease shall continue in full force and effect in accordance with its terms and
the Bank and Tenant shall be bound thereby. The Tenant agrees that any person to
which the Tenant shall attorn hereunder shall not be liable for any action or
omission of any prior landlord under the Lease including the Borrower, nor shall
such person be subject to any offsets or claims thereof or defenses which the
Tenant may have against any prior landlord, including the Borrower, except as
expressly provided under the Lease.

         7.       NONDISTURBANCE BY BANK. The Bank hereby agrees that for so
long as the Tenant duly and promptly performs all its obligations under the
Lease (within applicable notice and cure periods), the Bank will not, in taking
possession of or acquiring tide to the Premises or otherwise exercising its
rights under the Mortgage and/or the Collateral Assignment, whether through
foreclosure or otherwise, disturb the possession or other rights of the Tenant
under the Lease and shall recognize Tenant's rights under the Lease and accept
the Tenant as lessee under the terms and conditions and for the entire duration
of the term of the Lease. The Bank shall not, however, be bound by any
amendments or modifications of the Lease made without the written consent of the
Bank (which consent shall not be unreasonably withheld or delayed), or by any
liabilities of the Borrower arising under the Lease prior to the date the Tenant
has given notice thereof to the Bank nor shall the Bank be bound by any
representations or warranties given by Landlord under the Lease;

         Anything to the contrary herein notwithstanding, Tenant may not recover
from the taking award, or from any taking authority, except for moving expenses
separately awarded to Tenant which do not reduce Landlord's award, until the
Bank has been paid in full. In addition, the provisions of the Mortgage shall
control* with respect to the disposition and

                                        3


<PAGE>   37



application of insurance proceeds in the event of a casualty and disposition of
the taking award in the event of a taking of all or any portion of the Property.

*provided they are consistent with the provisions of Section 11.1 of the Lease,

         8.       EXTENSIONS AND RENEWALS. This Agreement shall include and
apply to any extensions and renewals of the term permitted by the Lease.

         9.       AMENDMENTS. This Agreement may not be waived, changed, or
discharged orally, but only by agreement in writing and signed by the Bank, the
Borrower, and the Tenant, and any oral waiver, change, or discharge of this
Agreement or any provision hereof shall be without authority and shall be of no
force and effect.

         10.      CAPTIONS. Paragraph captions are included herein for reference
only, and shall in no way constitute any part of this Agreement nor define or
limit any of the provisions hereof.

         11.      SEVERABILITY. The invalidity of any provision of this
Agreement, as determined by a court of competent jurisdiction, shall in no way
affect the validity of any other provisions hereof .

         12.      SUCCESSORS AND ASSIGNS. This Agreement shall be binding upon
each party's respective heirs, executors, administrators, representatives,
successors, and assigns and shall inure to the benefit of each party's
successors and assigns.

         13.      NOTICES. All notices, demands and other communications made in
this Agreement shall be made to the following addresses (each of which may be
changed upon seven (7) days written notice to all others) given by hand, or by
certified or registered mA return receipt requested, or by Federal Express or
other recognized same-day or overnight courier with receipt, as follows:

If the Bank:






with a copy to:





If to the Tenant:


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<PAGE>   38

with a copy to:





If to the Borrower:



With a copy to:



Any such notice shall be deemed received the earlier of (i) two (2) days after
the mailing of such notice in accordance with the terms and conditions and to
the addresses provided above, or (ii) the date on which the notice is delivered
by hand or by telegram to the address and to the individual provided above, or
(iii) one business day following delivery of such notice to such overnight
courier and addressed to the individual as provided above.

         14.      APPLICABLE LAW. This Agreement and all rights and obligations
hereunder, including matters of construction, validity and performance, shall be
governed by the laws of the Commonwealth of Massachusetts. The Tenant submits
itself to the jurisdiction of the courts of said Commonwealth for all purposes
with respect to this Agreement and the Tenant's relationship with the Bank.

         Witness the execution hereof under seal the day and year first above
written.



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