EXHIBIT 4C


                               ASECO CORPORATION
                            1993 OMNIBUS STOCK PLAN
              (Amended and Restated Effective as of June 14, 1996)

         1. Purpose. This 1993 Stock Plan (the "Plan") is intended to provide
incentives (a) to the officers and other employees of Aseco Corporation (the
"Company"), its parent (if any) and any present or future subsidiaries of the
Company (collectively, "Related Corporations") by providing them with
opportunities to purchase stock in the Company pursuant to options which qualify
as "incentive stock options" under Section 422 of the Internal Revenue Code of
1986, as amended (the "Code"), granted hereunder ("ISO" or "ISOs"); (b) to
directors, officers, employees and consultants of the Company and Related
Corporations by providing them with opportunities to purchase stock in the
Company pursuant to options granted hereunder which do not qualify as ISOs
("Non-Qualified Option" or "Non-Qualified Options"); (c) to directors, officers,
employees and consultants of the Company and Related Corporations by providing
them with awards of stock in the Company ("Awards"); and (d) to directors,
officers, employees and consultants of the Company and Related Corporations by
providing them with opportunities to make direct purchases of stock in the
Company ("Purchases"). Both ISOs and Non-Qualified Options are referred to
hereafter individually as an "Option" and collectively as "Options." As used
herein, the terms "parent" and "subsidiary" mean "parent corporation" and
"subsidiary corporation" as those terms are defined in Section 425 of the Code.

         2. Administration of the Plan. (a) The Plan shall be administered by
the Board of Directors of the Company (the "Board"). The Board may appoint a
Compensation Committee (the "Committee") of two or more of its members to
administer this Plan. In the event the Company registers any class of any equity
security pursuant to Section 12 of the Securities Exchange Act of 1934, as
amended (the "Exchange Act"), each member of the Committee shall be a
"disinterested person" as defined in Rule 16b-3 under the Exchange Act and an
"outside director" as defined in Section 162(m) of the Code. Subject to
ratification of the grant of each Option or Award and of the authorization of
each Purchase by the Board (if so required by applicable state law), and subject
to the terms of the Plan, the Committee, if so appointed, shall have the
authority to (i) determine the employees of the Company and Related Corporations
(from among the class of employees eligible under paragraph 3 to receive ISOs)
to whom ISOs may be granted, and to determine (from among the class of
individuals and entities eligible under paragraph 3 to receive Non-Qualified
Options and Awards and to make Purchases) to whom Non-Qualified Options or
Awards may be granted and who may make Purchases; (ii) determine the time or
times at which Options or Awards may be granted or Purchases made; (iii)
determine the option price of shares subject to each Option, which price with
respect to ISOs shall not be less than the minimum specified in paragraph 6, and
the purchase price of shares subject to each Purchase; (iv) determine whether
each Option granted shall be an ISO or a Non-Qualified Option; (v) determine
(subject to paragraph 7) the time or times when each Option shall become
exercisable and the duration of the exercise period; (vi) determine whether
restrictions such as repurchase options are to be imposed on shares subject to
Options, Awards and Purchases, and the nature of such restrictions, if any, and
(vii) interpret the Plan and prescribe and rescind rules and regulations
relating to it. If the Committee determines to issue a Non-Qualified Option, it

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shall take whatever actions it deems necessary, under Section 422 of the Code
and the regulations promulgated thereunder, to ensure that such Option is not
treated as an ISO. The interpretation and construction by the Committee of any
provisions of the Plan or of any Option, Award or authorization for any Purchase
granted under it shall be final unless otherwise determined by the Board. The
Committee may from time to time adopt such rules and regulations for carrying
out the Plan as it may deem best. No member of the Board or the Committee shall
be liable for any action or determination made in good faith with respect to the
Plan or any Option, Award or authorization for Purchase granted under it.

         (b) The Committee may select one of its members as its chairman, and
shall hold meetings at such time and places as it may determine. Acts by a
majority of the Committee, or acts reduced to or approved in writing by a
majority of the members of the Committee, shall be the valid acts of the
Committee. All references in this Plan to the Committee shall mean the Board if
there is no Committee so appointed. From time to time the Board may increase the
size of the Committee and appoint additional members thereof, remove members
(with or without cause), and appoint new members in substitution therefor, fill
vacancies however caused, or remove all members of the Committee and thereafter
directly administer the Plan.

         3. Eligible Employees and Others. ISOs may be granted to any officer or
other employee of the Company or any Related Corporation. Those directors of the
Company who are not employees may not be granted ISOs under the Plan. Non-
Qualified Options and Awards may be granted to, and Purchases may be made by,
any director (whether or not an employee), officer, employee or consultant of
the Company or any Related Corporation. The Committee may take into
consideration an optionee's individual circumstances in determining whether to
grant an ISO or a Non-Qualified Option or to authorize a Purchase. Granting of
any Option or Award to, or any Purchase by, any individual or entity shall
neither entitle that individual or entity to, nor disqualify him from,
participation in any other grant of Options or Awards, or in any other Purchase.

         4. Stock. The stock subject to Options, Awards and Purchases shall be
authorized but unissued shares of Common Stock of the Company, par value $.01
per share (the "Common Stock"), or shares of Common Stock re-acquired by the
Company in any manner. The aggregate number of shares which may be issued
pursuant to the Plan is 1,230,000, subject to adjustment as provided in
paragraph 13. Any such shares may be issued as ISOs, Non-Qualified Options or
Awards, or to persons or entities making Purchases, so long as the aggregate
number of shares so issued does not exceed such number, as adjusted. If any
Option granted under the Plan shall expire or terminate for any reason without
having been exercised in full or shall cease for any reason to be exercisable in
whole or in part, the unpurchased shares subject thereto shall again be
available for grants of Options or Awards and for Purchases under the Plan.

         5. Granting of Options. Options may be granted under the Plan at any
time on or after January 18, 1993 and prior to January 18, 2003. Any such grants
of ISOs shall be subject to the receipt, within 12 months of January 18, 1993,
of the approval of Stockholders as provided


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in paragraph 15. The date of grant of an Option under the Plan will be the date
specified by the Committee at the time it awards the Option; provided, however,
that such date shall not be prior to the date of award. The Committee shall have
the right, with the consent of the optionee, to convert an ISO granted under the
Plan to a Non-Qualified Option pursuant to paragraph 16. Any other provision of
the Plan notwithstanding, the number of shares of Common Stock for which options
may be granted in any fiscal year of the Company to any participant shall not
exceed 100,000.

         6. Minimum Option Price: ISO Limitations.

             A. The price per share specified in the agreement relating to each
ISO granted under the Plan shall not be less than the fair market value per
share of Common Stock on the date of such grant. In the case of an ISO to be
granted to an employee owning stock possessing more than ten percent of the
total combined voting power of all classes of stock of the Company or any
Related Corporation, the price per share specified in the agreement relating to
such ISO shall not be less than 110 percent of the fair market value of Common
Stock on the date of grant.

             B. In no event shall the aggregate fair market value (determined at
the time the option is granted) of Common Stock for which ISOs granted to any
employee are exercisable for the first time by such employee during any calendar
year (under all stock option plans of the Company and any Related Corporation)
exceed $100,000.

             C. If, at the time an Option is granted under the Plan, the
Company's Common Stock is publicly traded, "fair market value" shall be
determined as of the last business day for which the prices or quotes discussed
in this sentence are available prior to the date such Option is granted and
shall mean (i) the average (on that date) of the high and low prices of the
Common Stock on the principal national securities exchange on which the Common
Stock is traded, if such stock is then traded on a national securities exchange;
or (ii) the last reported sale price (on that date) of the Common Stock on the
NASDAQ National Market System, if the Common Stock is not then traded on a
national securities exchange; or (iii) the closing bid price (or average of bid
prices) last quoted (on that date) by an established quotation service for
over-the-counter securities, if the Common Stock is not reported on the NASDAQ
National Market System or on a national securities exchange. However, if the
Common Stock is not publicly traded at the time an Option is granted under the
Plan, "fair market value" shall be deemed to be the fair value of the Common
Stock as determined by the Committee after taking into consideration all factors
which it deems appropriate, including, without limitation, recent sale and offer
prices of the Common Stock in private transactions negotiated at arm's length.

         7. Option Duration. Subject to earlier termination as provided in
paragraphs 9 and 10, each Option shall expire on the date specified by the
Committee, but not more than ten years from the date of grant and in the case of
ISOs granted to an employee owning stock possessing more than ten percent of the
total combined voting power of all classes of stock of the Company or any
Related Corporation, not more than five years from date of grant. Subject to
earlier termination as provided in paragraphs 9 and 10, the term of each ISO
shall be the term set forth


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in the original instrument granting such ISO, except with respect to any part of
such ISO that is converted into a Non-Qualified Option pursuant to paragraph 16.

         8. Exercise of Option. Subject to the provisions of paragraphs 9
through 12, each Option granted under the Plan shall be exercisable as follows:

             A. The Option shall either be fully exercisable on the date of
grant or shall become exercisable thereafter in such installments as the
Committee may specify.

             B. Once an installment becomes exercisable it shall remain
exercisable until expiration or termination of the Option, unless otherwise
specified by the Committee.

             C. Each Option or installment may be exercised at any time or from
time to time, in whole or in part, for up to the total number of shares with
respect to which it is then exercisable.

             D. The Committee shall have the right to accelerate the date of
exercise of any installment; provided that the Committee shall not accelerate
the exercise date of any installment of any Option granted to any employee as an
ISO (and not previously converted into a Non-Qualified Option pursuant to
paragraph 16) if such acceleration would violate the annual vesting limitation
contained in Section 422(d) of the Code which provides generally that the
aggregate fair market value (determined at the time the option is granted) of
the stock with respect to which ISOs granted to any employee are exercisable for
the first time by such employee during any calendar year (under all plans of the
Company and any Related Corporation) shall not exceed $100,000.

         9. Termination of Employment. If an ISO optionee ceases to be employed
by the Company or any Related Corporation other than by reason of death or
disability as provided in paragraph 10, no further installments of his ISOs
shall become exercisable, and his ISOs shall terminate after the passage of 60
days from the date of termination of his employment, but in no event later than
on their specified expiration dates except to the extent that such ISOs (or
unexercised installments thereof) have been converted into Non-Qualified Options
pursuant to paragraph 16. Leave of absence with the written approval of the
Committee shall not be considered an interruption of employment under the Plan,
provided that such written approval contractually obligates the Company or any
Related Corporation to continue the employment of the employee after the
approved period of absence. Employment shall also be considered as continuing
uninterrupted during any other bona fide leave of absence (such as those
attributable to illness, military obligations or governmental service) provided
that the period of such leave does not exceed 90 days or, if longer, any period
during which such optionee's right to reemployment is guaranteed by statute.
Nothing in the Plan shall be deemed to give any grantee of any Option or Award,
or any person or entity entitled to make a Purchase, the right to be retained in
employment or other service by the Company or any Related Corporation for any
period of time. ISOs granted under the Plan shall not be affected by any change
of employment


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within or among the Company and Related Corporations, so long as the optionee
continues to be an employee of the Company or any Related Corporation. In
granting any Non-Qualified Option, the Committee may specify that such
Non-Qualified Option shall be subject to the restrictions set forth herein with
respect to ISOs, or to such other termination or cancellation provisions as the
Committee may determine.

         10. Death; Disability; Dissolution. If an optionee ceases to be
employed by the Company and all Related Corporations by reason of his death, any
Option of his may be exercised, to the extent of the number of shares with
respect to which he could have exercised it on the date of his death, by his
estate, personal representative or beneficiary who has acquired the Option by
will or by the laws of descent and distribution, at any time prior to the
earlier of the Option's specified expiration date or 180 days from the date of
the optionee's death.

         If an optionee ceases to be employed by the Company and all Related
Corporations by reason of his disability, he shall have the right to exercise
any Option held by him on the date of termination of employment, to the extent
of the number of shares with respect to which he could have exercised it on that
date, at any time prior to the earlier of the Option's specified expiration date
or 180 days from the date of the termination of the optionee's employment. For
the purposes of the Plan, the term "disability" shall have the meaning assigned
to it in Section 22(e)(3) of the Code or any successor statute.

         In the case of a partnership, corporation or other entity holding a
Non-Qualified Option, if such entity is dissolved, liquidated, becomes
insolvent or enters into a merger or acquisition with respect to which such
optionee is not the surviving entity, such Option shall terminate immediately.

         11. Assignability. No Option shall be assignable or transferable by the
optionee except by will or by the laws of descent and distribution, and during
the lifetime of the Optionee each Option shall be exercisable only by him.

         12. Terms and Conditions of Options. Options shall be evidenced by
instruments (which need not be identical) in such forms as the Committee may
from time to time approve. Such instruments shall conform to the terms and
conditions set forth in paragraphs 6 through 11 hereof and may contain such
other provisions as the Committee deems advisable which are not inconsistent
with the Plan, including restrictions applicable to shares of Common Stock
issuable upon exercise of Options. The Committee may from time to time confer
authority and responsibility on one or more of its own members and/or one or
more officers of the Company to execute and deliver such instruments. The proper
officers of the Company are authorized and directed to take any and all action
necessary or advisable from time to time to carry out the terms of such
instruments.

         13. Adjustments. Upon the happening of any of the following described
events, an optionee's rights with respect to Options granted to him hereunder
shall be adjusted as hereinafter provided:


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             A. In the event shares of Common Stock shall be sub-divided or
combined into a greater or smaller number of shares (other than the 1-for-2.4
reverse split of the Common Stock approved by the Board on January 18, 1992) or
if, upon a merger, consolidation, reorganization, split-up, liquidation,
combination, recapitalization or the like of the Company, the shares of Common
Stock shall be exchanged for other securities of the Company or of another
corporation, each optionee shall be entitled, subject to the conditions herein
stated, to purchase such number of shares of common stock or amount of other
securities of the Company or such other corporation as were exchangeable for the
number of shares of Common Stock which such optionee would have been entitled to
purchase except for such action, and appropriate adjustments shall be made in
the purchase price per share to reflect such subdivision, combination, or
exchange.

             B. In the event the Company shall issue any of its shares as a
stock dividend upon or with respect to the shares of stock of the class which
shall at the time be subject to option hereunder, each optionee upon exercising
an Option shall be entitled to receive (for the purchase price paid upon such
exercise) the shares as to which he is exercising his Option and, in addition
thereto (at no additional cost), such number of shares of the class or classes
in which such stock dividend or dividends were declared or paid, and such amount
of cash in lieu of fractional shares, as he would have received if he had been
the holder of the shares as to which he is exercising his Option at all times
between the date of grant of such Option and the date of its exercise.

             C. Notwithstanding the foregoing, any adjustments made pursuant to
subparagraph A or B shall be made only after the Committee, after consulting
with counsel for the Company, determines whether such adjustments with respect
to ISOs will constitute a "modification" of such ISOs as that term is defined in
Section 425 of the Code, or cause any adverse tax consequences for the holders
of such ISOs. No adjustments shall be made for dividends paid in cash or in
property other than securities of the Company.

             D. No fractional shares shall actually be issued under the Plan.
Any fractional shares which, but for this subparagraph D, would have been issued
to an optionee pursuant to an Option, shall be deemed to have been issued and
immediately sold to the Company for their fair market value, and the optionee
shall receive from the Company cash in lieu of such fractional shares.

             E. Upon the happening of any of the foregoing events described in
subparagraphs A or B above, the class and aggregate number of shares set forth
in paragraph 4 hereof which are subject to Options which previously have been or
subsequently may be granted under the Plan shall also be appropriately adjusted
to reflect the events specified in such subparagraphs. The Committee shall
determine the specific adjustments to be made under this paragraph 13, and
subject to paragraph 2, its determination shall be conclusive.

         14. Means of Exercising Options. An Option (or any part or installment
thereof) shall be exercised by giving written notice to the Company at its
principal office address. Such notice


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shall identify the Option being exercised and specify the number of shares as to
which such Option is being exercised, accompanied by full payment of the
purchase price therefor either (a) in United States dollars in cash or by check,
or (b) at the discretion of the Committee, through delivery of shares of Common
Stock having fair market value equal as of the date of the exercise to the cash
exercise price of the Option, or (c) at the discretion of the Committee, by
delivery of the optionee's personal recourse note bearing interest payable not
less than annually at no less than 100% of the lowest applicable Federal rate,
as defined in section 1274(d) of the Code, or (d) at the discretion of the
Committee, by any combination of (a), (b) and (c) above. If the Committee
exercises its discretion to permit payment of the exercise price of an ISO by
means of the methods set forth in clauses (b) or (c) of the preceding sentence,
such discretion shall be exercised in writing at the time of the grant of the
ISO in question. The holder of an Option shall not have the rights of a
shareholder with respect to the shares covered by his Option until the date of
issuance of a stock certificate to him for such shares. Except as expressly
provided above in paragraph 13 with respect to change in capitalization and
stock dividends, no adjustment shall be made for dividends or similar rights for
which the record date is before the date such stock certificates is issued.

         15. Term and Amendment of Plan. This Plan was adopted by the Board on
January 18, 1993, and was approved by the holders of a majority of the
outstanding voting stock of the Company on January 29, 1994. The Plan was
subsequently amended and restated by the Board effective January 12, 1994,
subject to approval of the amendments thereto by the stockholders of the Company
on or before January 12, 1995. The Plan shall expire on January 18, 2003 (except
as to Options outstanding on that date). The Board may terminate or amend the
Plan in any respect at any time, except that, any amendment that (a) increases
the total number of shares that may be issued under the Plan (except by
adjustment pursuant to paragraph 13); (b) changes the class of persons eligible
to participate in the Plan, or (c) materially increases the benefits to
participants under the Plan, shall be subject to approval by Stockholders
obtained within 12 months before or after the Board adopts a resolution
authorizing any of the foregoing amendments, and shall be null and void if such
approval is not obtained. Except as provided in the fourth sentence of this
paragraph 15, in no event may action of the Board of Stockholders alter or
impair the rights of an optionee, purchaser or Award recipient without his
consent, under any Option, Purchase or Award previously granted to or made by
him.

         16. Conversion of ISOs into Non-Qualified Options: Termination of ISOs.
The Committee, at the written request of any optionee, may in its discretion
take such actions as may be necessary to convert such optionee's ISOs (or any
installments or portions of installments thereof) that have not been exercised
on the date of conversion into Non-Qualified Options at any time prior to the
expiration of such ISOs, regardless of whether the optionee is an employee of
the Company or a Related Corporation at the time of such conversion. Such
actions may include, but not be limited to, extending the exercise period or
reducing the exercise price of the appropriate installments of such Options. At
the time of such conversion, the Committee (with the consent of the Optionee)
may impose such conditions on the exercise of the resulting Non-Qualified
Options as the Committee in its discretion may determine, provided that such
conditions shall not be inconsistent with this Plan. Nothing in the Plan shall
be deemed to give any optionee


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the right to have such optionee's ISOs converted into Non-Qualified Options, and
no such conversion shall occur until and unless the Board takes appropriate
action. The Committee, with the consent of the optionee, may also terminate any
portion of any ISO that has not been exercised at the time of such termination.

         17. Application of Funds. The proceeds received by the Company from the
sale of shares pursuant to Options granted and Purchases authorized under the
Plan shall be used for general corporate purposes.

         18. Governmental Regulation. The Company's obligation to sell and
deliver shares of the Common Stock under this Plan is subject to the approval of
any governmental authority required in connection with the authorization,
issuance or sale of such shares.

         19. Withholding of Additional Income Taxes. The Company, in accordance
with Section 3402(a) of the Code, may, upon exercise of a Non-Qualified Option,
the grant of an Award, the making of a Purchase of Common Stock for less than
its fair market value, or the making of a Disqualifying Disposition (as defined
in paragraph 20) require the optionee exercising such Option, Award recipient or
purchaser to pay additional withholding taxes in respect of the amount that is
considered compensation includible in such person's gross income.

         20. Notice to Company of Disqualifying Disposition. Each employee who
receives ISOs shall agree to notify the Company in writing immediately after the
employee makes a disqualifying disposition of any Common Stock received pursuant
to the exercise of an ISO (a "Disqualifying disposition"). Disqualifying
Disposition means any disposition (including any sale) of such stock before the
later of (a) two years after the employee was granted the ISO under which he
acquired such stock, or (b) one year after the employee acquired such stock by
exercising such ISO. If the Employee has died before such stock is sold, these
holding period requirements do not apply and no Disqualifying Disposition will
thereafter occur.

         21. Governing Laws; Construction. The validity and construction of the
Plan and the instruments evidencing Options, Awards and Purchases shall be
governed by the laws of The Commonwealth of Massachusetts. In construing this
Plan, the singular shall include the plural and the masculine gender shall
include the feminine and neuter, unless the context otherwise requires.


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