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                                                                   Exhibit 10.15
                                                                                
                            SPACETEC IMC CORPORATION
                                        
                              SEPARATION AGREEMENT
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     AGREEMENT made as of this 18th day of March, 1998 between SPACETEC IMC
CORPORATION, a Massachusetts corporation with a principal place of business at
The Boott Mills, 100 Foot of John Street, Lowell, Massachusetts 01852 (the
                                                                          
"Company"), and DENNIS GAIN, a former officer of the Company, residing at 30
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Boren Lane, Boxford, Massachusetts 01921(the "Employee").  In reliance on the
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mutual undertakings and consideration forth herein, the receipt and sufficiency
of which are hereby acknowledged, the parties agree as follows:

     1.  Severance Payments.  The Employee and the Company acknowledge that the
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Employee's employment with the Company is terminated effective as of February
24, 1998, and that on such date the Employee has resigned an officer and
employee of the Company and its subsidiaries (if applicable).  As complete and
unconditional satisfaction for the circumstances surrounding, and the
consequences of, the Employee's termination of employment and this resignation,
the Company shall make the following payments to the Employee:

         (a) the Company will pay $12,000 per month (payable bi-monthly in
     accordance with its normal payroll practices) for the 20-month period from
     March 1, 1998 until October 31, 1999; and

         (b) the Company will pay the monthly premium coverage associated for
     continued enrollment in the Company's Guardian Health Plan (family policy)
     (the "Plan"), or any successor plan, during the period from March 1, 1998
     until February 29, 2000; provided, however, the Company shall not be
     responsible for the life or disability coverage under such Plan.

     The Employee will advise and consult with the Company on an "as needed"
basis in return for the compensation paid to the Employee in clause (a) above.
The Employee acknowledges that the payments set forth in this Section 1 are in
addition to any legal obligations of the Company to the Employee set forth in
Section 2.  All amounts set forth above are subject to applicable federal, state
and local income, withholding, payroll and similar taxes.  The Employee shall be
responsible for the payment of all taxes on all payments hereunder.  After the
24-month period, the Employee will be entitled to participate at his expense in
the Company's Plan under applicable COBRA rules, to the extent permitted by law
and the provisions of the Plan.

     2.  Other Payments.  The Company will make the following payments to the
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Employee:

         (a) $4,615.35 of accrued vacation pay for 7-1/2 days (accrued but not
   used) as of February 24, 1998;

         (b) payment of authorized reimbursable expenses for which the Employee
   has provided the Company with appropriate documentation; and

         (c) payments of $1,000 per month (payable bi-monthly), for the period
   of twenty (20) months March 1, 1998 until October 31, 1999, as an automobile
   allowance.

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     All amounts set forth above in clauses (a) and (c) of this Section 2 are
subject to applicable (if any) federal, state and local taxes.  The Employee
shall purchase from the Company, for a purchase price of $28,571, a certain
Acura NSX automobile currently owned by the Company and used by the Employee.
This vehicle shall be sold to the Employee "AS IS," without warranty of any
kind, and the Employee shall be responsible for all further payments and
expenses associated with sale and use of the vehicle, including any vehicle
excise tax, insurance, gas, maintenance, repairs and other operational expenses.
Upon payment of the $28,571 purchase price for the vehicle, the Company shall
arrange for transfer of title to the Employee.  The vehicle shall be purchased
by the Employee within 15 business days of the execution of this Agreement.  If
the vehicle is not so purchased by the Employee within the 15-business-day
period, the Company shall have the right to deduct and offset from any payments
otherwise due to the Employee under this Agreement the purchase price of the
vehicle.

     3.  Settlement of Amounts Due Employee.  The amounts set forth in Sections
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1 and 2 shall be complete and unconditional payment, settlement, satisfaction
and accord with respect to all obligations and liabilities of the Company and
any of its subsidiaries (including their respective successors, assigns,
stockholders, officers, directors, employees and agents) to the Employee, and
all claims, obligations, causes of action and damages by the Employee against
the Company and/or any such other party concerning the Employee's employment by
the Company and/or  the circumstances surrounding its termination.  These claims
include without limitation, all claims for employment compensation; severance
payments; insurance policies; fringe benefits; accrued vacation pay; sick pay;
reimbursable expenses; obligations or commitments to grant stock options, issue
capital stock of the Company, or redeem or repurchase such capital stock;
performance bonuses; benefits and bonuses to be paid upon any sale, merger or
other acquisition of the Company; lodging, meals and automobile expenses; and
all other payments, compensations or reimbursements of every kind and
description, except for any benefits required by law to be paid to the Employee
under COBRA.  The Company shall have no further obligation, payment or
otherwise, under a certain "split dollar" insurance policy maintained by the
Company for the benefit of the Employee.  The Company and the Employee shall not
make, and the Company shall use reasonable efforts to prevent any of its
directors or employees from making, any disparaging remarks or negative comments
about each other in connection with the resignation of the Employee as an
officer of the Company and the circumstances surrounding his employment and his
termination.

     4.  Return of the Company Proprietary Materials.  Within fifteen (15) days
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of the execution of this Agreement, the Employee agrees to return to the Company
all materials, memoranda, sales brochures, credit cards, telephone charge cards,
manuals, building keys and passes, Company car and/or cellular phone, diskettes,
personal computers (including any laptop computer), dictaphone, business or
marketing plans, reports, projections, other computer equipment and software
programs, and all other Company information or property previously held or being
used by the Employee, including all tangible copies of confidential information
or trade secrets in the possession of Employee (collectively, the "Company
Materials").  The Employee agrees not to use any of the foregoing Company
Materials or incur any obligations on behalf of the Company from and after the
effective date of this Agreement.  The Company's credit card presently issued
under the Employee's personal name shall be returned and canceled and shall not
be used after the date hereof and the Employee shall promptly reimburse the
Company for any charges made by him on or after February 24, 1998, or the
Company may elect to offset such charges against payments to be made hereunder;
provided, however, that any credits on the balance of such card shall be
reimbursed to the Employee.  The Employee may retain, receive and use Company
Materials to the same extent as other directors retain, receive and use
materials and information about the Company in order to fulfill his obligations
as a director of the Company.
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     5.  Release of Claims and Causes of Action.  (a) As consideration for
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receipt of the amounts paid to the Employee pursuant to this Agreement above,
the Employee hereby absolutely and unconditionally releases and discharges the
Company, its subsidiaries and their respective successors, assigns,
stockholders, directors, officers, employees and agents (both in their official
and individual capacities), from and against any and all actions or causes of
action, suits, claims, complaints, contracts, liabilities, agreements, promises,
debts and damages, whether existing or contingent, known or unknown, at law or
in equity, relating to the Employee's employment by the Company or arising from
the circumstances surrounding his termination of employment (including claims
for attorneys' fees).  This release includes without limitation, any claims
arising under any federal or state law or regulation dealing with either
employment or employment discrimination such as those laws or regulations
concerning discrimination on the basis of age, race, color, religion, creed,
sex, ancestry, national origin, handicap status or status as a disabled or
Vietnam era veteran; any contract, whether oral or written, express or implied;
or common law.

     The Employee hereby agrees not to institute or join in any legal
proceedings against the Company or any such other party in connection with such
employment or the circumstances surrounding the termination of his employment,
including but not limited to any actions, charges or claims alleging violation
of any local, state or federal law, regulation or ordinance or any civil actions
alleging breach of contract, wrongful discharge, defamation, invasion of
privacy, or infliction of emotional distress.  The Employee agrees not only to
release and discharge the Company, its subsidiaries, and their respective
successors, assigns, stockholders, officers, directors, employees and agents
from any and all claims as stated above that the Employee could make on his own
behalf or on behalf of others, but also those claims which might be made by any
other person or organization on behalf of the Employee, and the Employee
specifically waives any right to become, and promises not to become, a member of
any class in a proceeding in which a claim or claims against the Company (and/or
its subsidiaries or their respective successors, assigns, stockholders,
officers, directors, employees and/or agents) are made involving any matters
arising out of the Employee's employment by or termination of his employment
with the Company.  The Employee agrees that once the Company has made the
payments specified in Sections 1 and 2, the Company will have satisfied any and
all legal and/or contractual obligations to him.

     (b) The Company hereby absolutely and unconditionally releases the Employee
from and against any and all claims, causes of action, damages, losses or
liabilities of any kind, of which the Company, relating to the Employee's
employment by the Company or arising from the circumstances surrounding the
termination of his employment (including claims for attorneys' fees).  The
Company hereby agrees not to institute or join in any legal proceedings against
the Employee in connection with such employment or the circumstances surrounding
the termination of his employment.

     (c) The foregoing releases shall not apply to any actions or omissions of
the Company or the Employee occurring after the date hereof relating to any
breach of this Agreement (or the other Agreements executed in connection
herewith) by any party.  The foregoing releases shall not apply to any right of
the Employee to claims for indemnification as a director or officer permitted
under the Company's charter or by-laws for actions taken by the Employee prior
to February 24, 1998 in good faith and in the reasonable belief that such
actions advanced and promoted the best interests of the Company (as further set
forth in the Company's By-laws).

     (d)  The Employee has been informed that since he is 40 years of age or
older, he has or might have specific rights and/or claims under the Age
Discrimination and Employment Act of 1967.  In consideration for the
compensation described in Section 1 hereof, the Employee specifically waives
such rights and/or claims to the extent that such rights and/or claims arose
prior to the date this Agreement 
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was executed. The Employee acknowledges that he has been advised by counsel
during the negotiation and preparation of this Agreement. 

     6.  Confidentiality; Non-Solicitation; and Non-Competition Covenants.  As
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consideration for the payments set forth in Section 1, the Employee shall
execute simultaneously with the execution of this Agreement, the Noncompetition,
Nondisclosure and Nonsolicitation Agreement (the "Noncompetition Agreement") set
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forth as Exhibit A attached hereto.  The restrictive covenants on noncompetition
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and nonsolicitation of employees and customers set forth in Sections 1 and 2 of
such Noncompetition Agreement shall be for the period from the date of execution
of this Agreement until February 29, 2000.  The Employee recognizes and agrees
that the enforcement of this Noncompetition Agreement is necessary to ensure the
preservation, protection and continuity of the confidential business
information, trade secrets and goodwill of the Company.  The Employee agrees
that, due to the proprietary nature of the Company's business, the restrictions
set forth in Sections 1, 2, 3 and 4 of the Noncompetition Agreement are
reasonable as to duration and scope, and are exchanged as express consideration
for the payments identified in Section 1.

   7.  Registration Rights; Stock Options.  (a)  If at any time the Company
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shall determine to register in a public offering for its own account (or the
account of selling stockholders) under the Securities Act of 1933 any of its
Common Stock, it shall send to the Employee written notice of such determination
and, if within 10 days after receipt of such notice, the Employee shall so
request in writing, the Company shall use its best efforts to include in such
registration statement all or any part of the shares of Common Stock held by the
Employee which he  requests to be registered.  This right shall not apply to a
registration of shares of Common Stock on Form S-4 or Form  S-8 (or their then
equivalents) relating to shares of Common Stock to be issued by the Company in
connection with any acquisition of any entity or other business combination
involving the Company, or shares of Common Stock issuable in connection with any
stock option, stock compensation or other employee benefits plan of the Company.

     If, in connection with any offering involving an underwriting of Common
Stock to be issued by the Company and/or selling stockholders, the managing
underwriter or the Company shall impose a limitation on the number of shares of
such Common Stock which may be included in any such registration statement
because, in its judgment, such limitation is necessary to effect an orderly
public distribution of the Common Stock and to maintain a stable market for the
securities of the Company, then the Company shall be obligated to include in
such registration statement only such limited portion (which may be none) of the
Employee's shares of Common Stock with respect to which the Employee has
requested inclusion hereunder, pro rata based upon the number of shares
originally requested for inclusion in such registration statement by all selling
stockholders (including the Employee) requesting inclusion thereunder.

     The Company shall bear the expenses of any filing of any registration,
including, but not limited to, printing, legal and accounting expenses,
Securities and Exchange Commission and NASD filing fees and all related "Blue
Sky" fees and expenses; provided, however, that the Company shall have no
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obligation to pay or otherwise bear any portion of the underwriters' commissions
or discounts attributable to the securities being offered and sold by the
Employee, or the fees and expenses of any counsel, tax advisor or accountant
selected by the Employee in connection with the registration of those
securities.  The rights granted to the Employee in this Section 7(a) shall
expire at such time as the Employee ceases to be an affiliate of the Company (as
determined under applicable federal securities laws, regulations and
interpretations), and the Employee is otherwise eligible to sell shares of
Common Stock without restriction as to volume pursuant to Rule 144(k) of the
Securities Act of 1933, as amended.
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                                       5

     (b)  The Employee's incentive stock options shall be converted to non-
qualified stock options, with vesting and expiration dates for each such option
to remain unchanged and unaffected by such conversion, except for options to
purchase 12,000 shares of Common Stock which are previously vested under  an
incentive stock option, number 00103, granted on April 29, 1994 at an exercise
price of $1.10 per share.  The Company acknowledges that the Employee has the
right to exercise such option for the three month period commencing from
February 24, 1998.

     8.  Other Agreements.  This Agreement and the Noncompetition Agreement
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executed in connection herewith constitute the entire agreement between the
parties concerning the termination of the Employee and supersedes any prior
negotiations, understandings or agreements concerning the subject matter hereof,
whether oral or written.  The Employee represents that, other than those
agreements specifically referenced herein, there are no agreements between him
and the Company or any of its subsidiaries.

     9.  Board Representation. The Company's Board of Directors shall, subject
         -------------------- 
to its fiduciary and other legal duties under the laws of the Commonwealth of
Massachusetts, the State of Delaware and the United state of America, nominate
the Employee for election to the Board at the next annual meeting of
stockholders of the Company or any special meeting of stockholders of the
Company (where directors are to be elected) held prior to the next such annual
meeting, and shall instruct all proxies named by the Board to vote for the
election of the Employee.

     10. General Provisions. This Agreement shall be governed by and construed
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in accordance with the laws of the Commonwealth of Massachusetts. All notices,
if any, to be provided hereunder shall be provided by (i) first class mail,
postage prepaid; (ii) by express overnight courier service, or (iii) by hand
delivery, to the parties at their addresses set forth above. This Agreement may
be amended or rescinded only upon the written consent of the Company and the
Employee. The invalidity or unenforceability of any provision of this Agreement
shall not affect the other provisions of this Agreement but this Agreement shall
be revised, construed and reformed to the fullest extent possible to effectuate
the purposes of this Agreement. This Agreement shall be binding upon and inure
to the benefit of the Company and the Employee and their respective heirs,
successors and assigns. This Agreement may be executed in any number of
counterparts, all of which taken together shall constitute one and the same
instrument. The parties agree that the Company will not have an adequate remedy
if the Employee fails to comply with Sections 4, 5 and 6 hereof and Sections 1,
2, 3 and 4 of the Noncompetition Agreement and that damages will not be readily
ascertainable, and that in the event of such failure, the Employee shall not
oppose any application by the Company requiring a decree of specific performance
or an injunction enjoining a breach of this Agreement. If the Employee fails to
cure any material breach of any of his obligations hereunder, including Sections
4, 5 and 6 hereof and Sections 1, 2, 3 and 4 of the Noncompetition Agreement,
within fifteen (15) days after receipt of notice of such breach from the
Company, he shall forfeit all right to severance payments. Each party has
obtained independent legal advice, and the Employee freely and voluntarily
consulted legal counsel for review of this Agreement. The Employee represents
that he has read the foregoing Agreement, fully understands the terms and
conditions of such Agreement, and is voluntarily executing the same. In entering
into this Agreement, the Employee does not rely on any representation, promise
or inducement made by the Company, with the exception of the consideration
described in this document. The Employee represents that he has not willfully
breached any of the terms of any confidentiality, assignment of inventions, non-
solicitation or non-competition agreement to which he and the Company are
parties. From and after the date of this Agreement, the Company and the Employee
agree to execute 
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                                       6


and deliver such instruments or documents as may be necessary or appropriate to
carry out and effect fully the intent and purposes of this Agreement.

     IN WITNESS WHEREOF, the parties hereto have caused this Separation
Agreement to be executed as of the date first above written as an instrument
under seal.

SPACETEC IMC CORPORATION              EMPLOYEE:

By: 
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                                      Dennis Gain

Title:
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