Exhibit 10.1
                                                                    ------------

                                  PROCEPT, INC.

                                 1989 Stock Plan
                                 ---------------

As amended through April 16, 1996 and
As further amended by the Board of Directors on
  March 17, 1997 and approved by the Stockholders
  on June 16, 1997
As further amended by the Board of Directors
  on April 6, 1998 and approved by the
  Stockholder on May 18, 1998.


     1. Purpose. This 1989 Stock Plan (the "Plan") is intended to provide
incentives: (a) to the officers and other employees of Procept, Inc. (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 granted
hereunder which qualify as "incentive stock options" under Section 422(b) of the
Internal Revenue Code of 1986, as amended (the "Code") ("ISO" or "ISOs"); (b) to
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 officers, employees and consultants of the
Company and Related Corporations by providing them with awards of stock in the
Company ("Awards"); and (d) to 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". Options, Awards and authorizations to make Purchases
are referred to hereafter collectively as "Stock Rights". As used herein, the
terms "parent" and "subsidiary" mean "parent corporation" and "subsidiary
corporation", respectively, as those terms are defined in Section 424 of the
Code.

     2. Administration of the Plan.
        ---------------------------

        A. Board or Committee Administration. The Plan shall be administered by
the Board of Directors of the Company (the "Board"). The Board may appoint a
Stock Plan Committee (the "Committee") of three or more of its members to
administer this Plan. The members of such Committee shall be "disinterested"
within the meaning of Rule 16b-3 promulgated under the Securities Exchange Act
of 1934, as amended. Hereinafter, all references in this Plan to the "Committee"
shall mean the Board if no Committee has been appointed. Subject to ratification
of the grant or authorization of each Stock Right by the Board (if so required
by applicable state law), and subject to the terms of the Plan, the Committee
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, Awards and authorizations to make Purchases may be granted; (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 shall not be less than the minimum price 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

                                       1
<PAGE>

and rescind rules and regulations relating to it. If the Committee determines to
issue a Non-Qualified Option, it 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 Stock
Right 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 Stock Right granted under it.

        B. Committee Actions. 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. 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 employee of
the Company or any Related Corporation. Those officers of the Company who are
not employees may not be granted ISOs under the Plan. Non-Qualified Options,
Awards and authorizations to make Purchases may be granted to any employee or
officer (whether or not also an employee) or consultant of the Company or any
Related Corporation. The Committee may take into consideration a recipient's
individual circumstances in determining whether to grant an ISO, a Non-Qualified
Option, an Award or an authorization to make a Purchase. Granting of any Stock
Right to any individual or entity shall neither entitle that individual or
entity to, nor disqualify such individual or entity from, participating in any
other grant of Stock Rights.

     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 reacquired by the
Company in any manner. The aggregate number of shares which may be issued
pursuant to the Plan is 1,500,000 (after giving effect to the June 1, 1998
ten-for-one reverse split). The aggregate number of shares which may be issued
pursuant to the Plan is subject to further 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 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, or if
the Company shall reacquire any unvested shares issued pursuant to Options,
Awards or Purchases, the unpurchased shares subject to such Options and any
unvested shares so reacquired by the Company shall again be available for grants
of Stock Rights under the Plan.

     5. Granting of Stock Rights. Stock Rights may be granted under the Plan at
any time on or after April 18, 1989 and prior to July 1, 2007. The date of grant
of a Stock Right under the Plan will be the date specified by the Committee at
the time it grants the Stock Rights; provided, however, that such date shall not
be prior to the date on which the Committee acts to approve the grant. 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.


                                       2
<PAGE>

     6. Minimum Option Price; ISO Limitations.
        --------------------------------------

        A. Price for Non-Qualified Options. The exercise price per share
specified in the agreement relating to each Non-Qualified Option granted under
the Plan shall in no event be less than the lesser of (i) the book value per
share of Common Stock as of the end of the fiscal year of the Company
immediately preceding the date of such grant, or (ii) fifty percent (50%) of the
fair market value per share of Common Stock on the date of such grant.

        B. Price of ISOs. The exercise 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 (10%) 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 one hundred ten percent
(110%) of the fair market value per share of Common Stock on the date of grant.

        C. $100,000 Annual Limitation on ISOs. Each eligible employee may be
granted ISOs only to the extent that, in the aggregate under this Plan and all
incentive stock option plans of the Company and any Related Corporation, such
ISOs do not become exercisable for the first time by such employee during any
calendar year in a manner which would entitle the employee to purchase more than
$100,000 in fair market value (determined at the time the ISOs were granted) of
Common Stock in that year. Any options granted to an employee in excess of such
amount will be granted as Non-Qualified Options.

        D. Determination of Fair Market Value. 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 the Common 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 SmallCap 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 SmallCap Market System. 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 (i) ten years and one day from the date of grant in
the case of Non-Qualified Options, (ii) ten years from the date of grant in the
case of ISOs generally, and (iii) five years from the date of grant in the case
of ISOs granted to an employee owning stock possessing more than ten percent
(10%) of the total combined voting power of all classes of stock of the Company
or any Related Corporation. Subject to earlier termination as provided in
paragraphs 9 and 10, the term of each ISO shall be the term set forth 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.


                                       3
<PAGE>

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

        C. Partial Exercise. 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. Acceleration of Vesting. The Committee shall have the right to
accelerate the date of exercise or vesting of any installment of any Option;
provided that the Committee shall not, without the consent of an optionee,
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, as described in paragraph
6(C).

     9.  Termination of Employment. If an ISO optionee ceases to be employed by
the Company and all Related Corporations other than by reason of death or
disability as defined in paragraph 10, no further installments of such
optionee's ISOs shall become exercisable or vested, and such optionee's ISOs
shall terminate after the passage of ninety (90) days from the date of
termination of such optionee's 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. Employment shall be considered as continuing uninterrupted during
any 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 reemployment is guaranteed by statute. A bona fide
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 optionee after the approved period of absence.
ISOs granted under the Plan shall not be affected by any change of employment
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. Nothing
in the Plan shall be deemed to give any grantee of any Stock Right the right to
be retained in employment or other service by the Company or any Related
Corporation for any period of time.

     10. Death; Disability.
         ------------------

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

         B. Disability. If an ISO optionee ceases to be employed by the Company
and all Related Corporations by reason of such optionee's disability, such
optionee shall have the right to


                                       4
<PAGE>

exercise any ISO held by such optionee on the date of termination of employment,
to the extent of the number of shares with respect to which such optionee could
have exercised it on that date, at any time prior to the earlier of the
specified expiration date of the ISO or 180 days from the date of the
termination of such optionee's employment. For the purposes of the Plan, the
term "disability" shall mean "permanent and total disability" as defined in
Section 22(e)(3) of the Code or successor statute.

     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 such
optionee.

     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. 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
and cancellation provisions as the Committee may determine. 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 occurrence of any of the following events, an
optionee's rights with respect to Options granted to such optionee hereunder
shall be adjusted as hereinafter provided, unless otherwise specifically
provided in the written agreement between the optionee and the Company relating
to such Option:

         A. Stock Dividends and Stock Splits. If the shares of Common Stock
shall be subdivided or combined into a greater or smaller number of shares or if
the Company shall issue any shares of Common Stock as a stock dividend on its
outstanding Common Stock, the number of shares of Common Stock deliverable upon
the exercise of Options shall be appropriately increased or decreased
proportionately, and appropriate adjustments shall be made in the purchase price
per share to reflect such subdivision, combination or stock dividend.

         B. Consolidation or Mergers. If the Company is to be consolidated with
or acquired by another entity in a merger, sale of all or substantially all of
the Company's assets or otherwise (an "Acquisition"), the Committee or the board
of directors of any entity assuming the obligations of the Company hereunder
(the "Successor Board"), shall, as to outstanding Options, either (i) make
appropriate provision for the continuation of such Options by substituting on an
equitable basis for the shares then subject to such Options the consideration
payable with respect to the outstanding shares of Common Stock in connection
with the Acquisition; or (ii) upon written notice to the optionees, provide that
all Options must be exercised, to the extent then exercisable, within a
specified number of days of the date of such notice, at the end of which period
the Options shall terminate; or (iii) terminate all Options in exchange for a
cash payment equal to the excess of the fair market value of the shares subject
to such Options (to the extent then exercisable) over the exercise price
thereof.

         C. Recapitalization or Reorganization. In the event of a
recapitalization or reorganization of the Company (other than a transaction
described in subparagraph B above) pursuant to which securities of the Company
or of another corporation are issued with respect to the outstanding



                                       5
<PAGE>

shares of Common Stock, an optionee upon exercising an Option shall be entitled
to receive for the purchase price paid upon such exercise the securities such
optionee would have received if such optionee had exercised such optionee's
Option prior to such recapitalization or reorganization.

         D. Modification of ISOs. Notwithstanding the foregoing, any adjustments
made pursuant to subparagraphs A, B or C with respect to ISOs shall be made only
after the Committee, after consulting with counsel for the Company, determines
whether such adjustments would constitute a "modification" of such ISOs (as that
term is defined in Section 424 of the Code) or would cause any adverse tax
consequences for the holders of such ISOs. If the Committee determines that such
adjustments made with respect to ISOs would constitute a modification of such
ISOs, it may refrain from making such adjustments.

         E. Dissolution or Liquidation. In the event of the proposed dissolution
or liquidation of the Company, each Option will terminate immediately prior to
the consummation of such proposed action or at such other time and subject to
such other conditions as shall be determined by the Committee.

         F. Issuances of Securities. Except as expressly provided herein, no
issuance by the Company of shares of stock of any class, or securities
convertible into shares of stock of any class, shall affect, and no adjustment
by reason thereof shall be made with respect to, the number or price of shares
subject to Options. No adjustments shall be made for dividends paid in cash or
in property other than securities of the Company.

         G. Fractional Shares. No fractional shares shall be issued under the
Plan and the optionee shall receive from the Company cash in lieu of such
fractional shares.

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

If any person or entity owning restricted Common Stock obtained by exercise of a
Stock Right made hereunder receives shares or securities or cash in connection
with a corporate transaction described in subparagraphs A, B or C above as a
result of owning such restricted Common Stock, such shares or securities or cash
shall be subject to all of the conditions and restrictions applicable to the
restricted Common Stock with respect to which such shares or securities or cash
were issued, unless otherwise determined by the Committee or the Successor
Board.

     14. Means of Exercising Stock Rights. A Stock Right (or any part or
installment thereof) shall be exercised by giving written notice to the Company
at its principal office address. Such notice shall identify the Stock Right
being exercised and specify the number of shares as to which such Stock Right 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 a
fair market value equal as of the date of the exercise to the cash exercise
price of the Stock Right, or (c) at the discretion of the Committee, by delivery
of the grantee's personal recourse note being 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), (c), or (d) of the preceding


                                       6
<PAGE>

sentence, such discretion shall be exercised in writing at the time of the grant
of the ISO in question. The holder of a Stock Right shall not have the rights of
a shareholder with respect to the shares covered by such holder's Stock Right
until the date of issuance of a stock certificate to such holder for such
shares. Except as expressly provided above in paragraph 13 with respect to
changes 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 certificate is issued.

     15. Term and Amendment of Plan. This Plan was adopted by the Board on April
18, 1989, subject (with respect to the validation of ISOs granted under the
Plan) to approval of the Plan by the stockholders of the Company at the next
Meeting of Stockholders or, in lieu thereof, by written consent. If the approval
of stockholders is not obtained by April 18, 1990, any grants of ISOs under the
Plan made prior to that date will be rescinded. The Plan shall expire on July 1,
2007 (except as to Options outstanding on that date). Subject to the provisions
of paragraph 5 above, Stock Rights may be granted under the Plan prior to the
date of stockholder approval of the Plan. The Board may terminate or amend the
Plan in any respect at any time, except that, without the approval of the
stockholders obtained within 12 months before or after the Board adopts a
resolution authorizing any of the following actions: (a) the total number of
shares that may be issued under the Plan may not be increased (except by
adjustment pursuant to paragraph 13); (b) the provisions of paragraph 3
regarding eligibility for grants of ISOs may not be modified; (c) the provisions
of paragraph 6(B) regarding the exercise price at which shares may be offered
pursuant to ISOs may not be modified (except by adjustment pursuant to paragraph
13); and (d) the expiration date of the Plan may not be extended. Except as
otherwise provided in this paragraph 15, in no event may action of the Board or
stockholders alter or impair the rights of a grantee, without such grantee's
consent, under any Stock Right previously granted to such grantee.

     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 the right to have such optionee's ISOs converted
into Non-Qualified Options, and no such conversion shall occur until and unless
the Committee 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. Upon the 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, the making of a Disqualifying
Disposition (as defined in paragraph 20) or the vesting of restricted Common
Stock acquired on the exercise of a Stock Right hereunder, the Company, in
accordance with Section


                                       7
<PAGE>

3402(a) of the Code, may require the optionee, Award recipient or purchaser to
pay additional withholding taxes in respect of the amount that is considered
compensation includable in such person's gross income. The Committee in its
discretion may condition (i) the exercise of an Option, (ii) the grant of an
Award, (iii) the making of a Purchase of Common Stock for less than its fair
market value, or (iv) the vesting of restricted Common Stock acquired by
exercising a Stock Right, on the grantee's payment of such additional
withholding taxes.

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

     21. Governing Law; Construction. The validity and construction of the Plan
and instruments evidencing Stock Rights shall be governed by the laws of the
State of Delaware, or the laws of any jurisdiction in which the Company or its
successors in interest may be organized. In construing this Plan, the singular
shall include the plural.



                                       8