Spacetec IMC Corporation

                  Amended and Restated 1993 Stock Option Plan

           As adopted by the Board of Directors on September 29, 1995
              and approved by the Stockholders on October 6, 1995


     This 1993 Stock Option Plan (the "Plan") is intended to encourage ownership
of Common Stock, $.01 par value (the "Stock") of Spacetec IMC Corporation (the
"Company") by its officers, employees and consultants so as to provide
additional incentives to promote the success of the Company through the grant of
Incentive Stock Options and Nonstatutory Stock Options (as such terms are
defined in Section 3(a) below (collectively, "Options").

     1.   Administration of the Plan.
          -------------------------- 

     The administration of the Plan shall be under the general supervision of
any committee of the Board appointed by the Board to administer the Plan, the
members of which are 'disinterested persons' within the meaning of Rule 16b-3
under the Securities Exchange Act of 1934, as amended, or any successor
provision (the "Rule") to the extent necessary to comply with the Rule (the
"Compensation Committee"). Within the limits of the Plan, the Compensation
Committee shall determine the individuals to whom, and the times at which,
Options shall be granted, the type of Option to be granted, the duration of each
Option, the price and method of payment for each Option, and the time or times
within which (during its term) all or portions of each Option may be exercised.
The Compensation Committee may establish such rules as it deems necessary for
the proper administration of the Plan, make such determinations and
interpretations with respect to the Plan and Options granted under it as may be
necessary or desirable and include such further provisions or conditions in
Options granted under the Plan as it deems advisable.  To the extent permitted
by law, the Compensation Committee may delegate its authority under the Plan to
a sub-committee of the Compensation Committee.

     2.   Shares Subject to the Plan.
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          (a)  Number and Type of Shares.  The aggregate number of shares of
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Stock of the Company which may be optioned under the Plan is 1,600,000 shares.
In the event that the Compensation Committee in its discretion determines that
any stock dividend, split-up, combination or reclassification of shares,
recapitalization or other similar capital change affects the Stock such that
adjustment is required in order to preserve the benefits or potential benefits
of the Plan or any Option granted under the Plan, the maximum aggregate number
and kind of shares or securities of the Company as to which Options may be
granted under the Plan and as to which Options then outstanding shall be
exercisable, and the option price of such Options, shall be appropriately
adjusted by the Compensation Committee (whose determination shall be conclusive)
so that the proportionate number of shares or other securities as to which
Options may be granted and the proportionate interest of holders of outstanding
Options shall be maintained as before the occurrence of such event.

          (b)  Effect of Certain Transactions.  In the event of a consolidation
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or merger of the Company with another corporation, or the sale or exchange of
all or substantially all of the assets of the Company, or a reorganization or
liquidation of the Company, each holder of an outstanding Option shall be
entitled to receive upon exercise and payment in accordance with the terms of
the

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Option the same shares, securities or property as he would have been entitled to
receive upon the occurrence of such event if he had been, immediately prior to
such event, the holder of the number of shares of Stock purchasable under his
Option; provided, however, that in lieu of the foregoing the Board of Directors
of the Company (the "Board") may upon written notice to each holder of an
outstanding Option provide that such Option shall terminate on a date not less
than 20 days after the date of such notice unless theretofore exercised.  In
connection with such notice, the Board may in its discretion accelerate or waive
any deferred exercise period.

          (c)  Restoration of Shares.  If any Option expires or is terminated
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unexercised or is forfeited for any reason or settled in a manner that results
in fewer shares outstanding than were initially awarded, including without
limitation the surrender of shares in payment of the Option exercise price or
any tax obligation thereon, the shares subject to such Option or so surrendered,
as the case may be, to the extent of such expiration, termination, forfeiture or
decrease, shall again be available for granting Options under the Plan, subject,
however, in the case of Incentive Stock Options, to any requirements under the
Code (as defined below).

          (d)  Reservation of Shares.  The Company shall at all times while the
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Plan is in force reserve such number of shares of Stock as will be sufficient to
satisfy the requirements of the Plan.  Shares issued under the Plan may consist
in whole or in part of authorized but unissued shares or treasury shares.

     3.   Grant of Options; Eligible Persons
          ----------------------------------

          (a)  Types of Options.  Options shall be granted under the Plan either
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as incentive stock options ("Incentive Stock Options"), as defined in Section
422 of the Internal Revenue Code of l986, as amended (the "Code") or as Options
which do not meet the requirements of Section 422 ("Nonstatutory Stock
Options").  Options may be granted from time to time by the Compensation
Committee, within the limits set forth in Sections l and 2 of the Plan, to all
employees of the Company or of any parent corporation or subsidiary corporation
of the Company (as defined in Sections 424(e) and (f), respectively, of the
Code), and, with regard to Nonstatutory Stock Options, to all employees and
consultants of the Company or of any such parent corporation or subsidiary
corporation.

          (b)  Date of Grant.  The date of grant for each Option shall be the
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date on which it is approved by the Compensation Committee, or such later date
as the Compensation Committee may specify.  No Options shall be granted
hereunder after ten years from the date on which the Plan was approved by the
Board.

          (c)  Automatic Awards.  The Compensation Committee may provide for the
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automatic award of an Option upon the delivery of shares to the Company in
payment of an Option for up to the number of shares so delivered.

     4.   Form of Options.
          --------------- 

     Options granted hereunder shall be evidenced by a writing delivered to the
optionee specifying the terms and conditions thereof and containing such other
terms and conditions not inconsistent with the provisions of the Plan as the
Compensation Committee considers necessary or advisable to achieve the purposes
of the Plan or comply with applicable tax and regulatory laws and accounting
principles.  The form of such Options may vary among optionees.

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     5.   Option Price.
          ------------ 

     In the case of Incentive Stock Options, the price at which shares may from
time to time be optioned shall be determined by the Compensation Committee,
provided that such price shall not be less than the fair market value of the
Stock on the date of granting as determined in good faith by the Compensation
Committee; and provided further that no Incentive Stock Option shall be granted
to any individual who is ineligible to be granted an Incentive Stock Option
because his ownership of stock of the Company or its parent or subsidiary
corporations exceeds the limitations set forth in Section 422(b)(6) of the Code
unless such option price is at least ll0% of the fair market value of the Stock
on the date of grant.

     In the case of Nonstatutory Stock Options, the price at which shares may
from time to time be optioned shall be determined by the Compensation Committee.

     The Compensation Committee may in its discretion permit the option price to
be paid in whole or in part by a note or in installments or with shares of Stock
of the Company or such other lawful consideration as the Compensation Committee
may determine.

     6.   Term of Option and Dates of Exercise.
          ------------------------------------ 

          (a)  Exercisability.  The Compensation Committee shall determine the
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term of all Options, the time or times that Options are exercisable and whether
they are exercisable in installments; provided, however, that the term of each
non-statutory stock option granted under the Plan shall not exceed a period of
eleven years from the date of its grant and the term of each Incentive Stock
Option granted under the Plan shall not exceed a period of ten years from the
date of its grant, provided that no Incentive Stock Option shall be granted to
any individual who is ineligible to be granted such Option because his ownership
of stock of the Company or its parent or subsidiary corporations exceeds the
limitations set forth in Section 422(b)(6) of the Code unless the term of his
Incentive Stock Option does not exceed a period of five years from the date of
its grant.  In the absence of such determination, the Option shall be
exercisable at any time or from time to time, in whole or in part, during a
period of ten years from the date of its grant or, in the case of an Incentive
Stock Option, the maximum term of such Option.

          (b)  Effect of Disability, Death or Termination of Employment.  The
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Compensation Committee shall determine the effect on an Option of the
disability, death, retirement or other termination of employment of an optionee
and the extent to which, and during the period which, the optionee's estate,
legal representative, guardian, or beneficiary on death may exercise rights
thereunder.  Any beneficiary on death shall be designated by the optionee, in
the manner determined by the Compensation Committee, to exercise rights of the
optionee in the case of the optionee's death.

          (c)  Other Conditions.  The Compensation Committee may impose such
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conditions with respect to the exercise of Options, including conditions
relating to applicable federal or state securities laws, as it considers
necessary or advisable.

          (d)  Withholding.  The optionee shall pay to the Company, or make
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provision satisfactory to the Compensation Committee for payment of, any taxes
required by law to be withheld in respect of any Options under the Plan no later
than the date of the event creating the tax liability.  In the Compensation
Committee's discretion, such tax obligations may be paid in whole or in part in
shares of Stock, including shares retained from the exercise of the Option
creating the tax obligation, valued at the fair market value of the Stock on the
date of delivery to the Company as determined in

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good faith by the Compensation Committee.  The Company and any parent
corporation or subsidiary corporation of the Company (as defined in Sections
424(e) and (f), respectively, of the Code) may, to the extent permitted by law,
deduct any such tax obligations from any payment of any kind otherwise due to
the optionee.

          (e)  Amendment of Options.  The Compensation Committee may amend,
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modify or terminate any outstanding Option, including substituting therefor
another Option of the same or different type, changing the date of exercise or
realization and converting an Incentive Stock Option to a Nonstatutory Stock
Option, provided that the optionee's consent to such action shall be required
unless the Compensation Committee determines that the action, taking into
account any related action, would not materially and adversely affect the
optionee.

     7.   Non-transferability.
          ------------------- 

     Options granted under the Plan shall not be transferable by the holder
thereof otherwise than by will or the laws of descent and distribution, and
shall be exercisable, during the holder's lifetime, only by him or her, except
as may otherwise be permitted by the Rule.

     8.   No Right to Employment.
          ---------------------- 

     No persons shall have any claim or right to be granted an Option, and the
grant of an Option shall not be construed as giving an optionee the right to
continued employment.  The Company expressly reserves the right at any time to
dismiss an optionee free from any liability or claim under the Plan, except as
specifically provided in the applicable Option.

     9.   No Rights as a Shareholder.
          -------------------------- 

     Subject to the provisions of the applicable Option, no optionee or any
person claiming through an optionee shall have any rights as a shareholder with
respect to any shares of Stock to be distributed under the Plan until he or she
becomes the holder thereof.

     10.  Amendment or Termination.
          ------------------------ 

     The Board may amend or terminate the Plan at any time, provided that no
amendment shall be made without stockholder approval if such approval is
necessary to comply with any applicable tax or regulatory requirement, including
any requirement for exemptive relief under Section 16(b) of the Securities
Exchange Act of 1934, or any successor provision.

     11.  Stockholder Approval.
          -------------------- 

     The Plan is subject to approval by the stockholders of the Company by the
affirmative vote of the holders of a majority of the shares of capital stock of
the Company entitled to vote thereon and present or represented at a meeting
duly held in accordance with the laws of the Commonwealth of Massachusetts, or
by any other action that would be given the same effect under the laws of such
jurisdiction, which action in either case shall be taken within twelve (12)
months from the date the Plan was adopted by the Board.  In the event such
approval is not obtained, all Options granted under the Plan shall be void and
without effect.

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     12.  Governing Law.
          ------------- 

     The provisions of the Plan shall be governed by and interpreted in
accordance with the laws of the Commonwealth of Massachusetts.

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