LIGHTBRIDGE, INC.

                        1996 INCENTIVE AND NON-QUALIFIED
                               STOCK OPTION PLAN


SECTION 1. PURPOSE

   This 1996 Incentive and Non-Qualified Stock Option Plan (the "Plan") is
intended as a performance incentive for officers and employees of Lightbridge,
Inc., a Delaware corporation (the "Company"), or its Subsidiaries (as
hereinafter defined) and for certain other individuals providing services to or
acting as directors of the Company or its Subsidiaries, to enable the persons to
whom options are granted (an "Optionee" or "Optionees") to acquire or increase a
proprietary interest in the Company and its success.  The Company intends that
this purpose will be effected by the granting of incentive stock options
("Incentive Options") as defined in Section 422 of the Internal Revenue Code of
1986, as amended (the "Code"), and other stock options ("Non-Qualified Options")
under the Plan.  The term "Subsidiaries" means any corporations in which stock
possessing 50% or more of the total combined voting power of all classes of
stock of such corporation or corporations is owned directly or indirectly by the
Company.

SECTION 2. OPTIONS TO BE GRANTED AND ADMINISTRATION

   2.1.  Options to be Granted.  Options granted under the Plan may be either
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Incentive Options or Non-Qualified Options.  If an option is intended to be an
Incentive Option, and if for any reason such option (or any portion thereof)
shall not qualify as an Incentive Option, then, to the extent of such
nonqualification, such option (or portion thereof) shall be regarded as a Non-
Qualified Option appropriately granted under the Plan provided that such option
(or portion thereof) otherwise meets the Plan's requirements relating to Non-
Qualified Options.  The Board may, as a condition of grant, require the Optionee
to execute a confidentiality and noncompetition agreement with the Company.

   2.2.  Administration.  This Plan shall be administered by the Compensation
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Committee or any other committee of the Board of Directors of the Company (the
"Board"), consisting of two or more "Outside Directors" (such committee may
hereinafter be referred to as the "Plan Administrator").  As used herein, the
term "Outside Director" means any director who:  (i) is not an employee of the
Company or of any "affiliated group" (as such term is defined in Section 1504(a)
of the Code) which includes the Company (an "Affiliate"); (ii) is not a former
employee of the Company or any Affiliate who is receiving compensation for prior
services (other than benefits under a tax-qualified retirement plan) during the
Company's or any Affiliate's taxable year; (iii) has not been an officer of the
Company or any Affiliate; and (iv) does not receive remuneration from the
Company or any Affiliate, either directly or indirectly, in any capacity other
than as a director. 

 
   Except as specifically reserved to the Board under the terms of the Plan, the
Plan Administrator shall have full and final authority to operate, manage and
administer the Plan on behalf of the Company.  This authority includes, but is
not limited to:  (i) the power to grant options conditionally or
unconditionally; (ii) the power to prescribe the form or forms of the
instruments evidencing options granted under this Plan; (iii) the power to
interpret the Plan; (iv) the power to provide regulations for the operation of
the incentive features of the Plan, and otherwise to prescribe regulations for
interpretation, management and administration of the Plan; (v) the power to
delegate to other persons the responsibility for performing ministerial acts in
furtherance of the Plan's purpose; (vi) the power to make, in its sole
discretion, changes to any outstanding option granted under the Plan, including
the power to reduce the exercise price, to accelerate the vesting schedule, or
to extend the expiration date; and (vii) the power to engage the services of
persons or organizations in furtherance of the Plan's purpose, including but not
limited to banks, insurance companies, brokerage firms and consultants.

   In addition, as to each option, the Plan Administrator shall have full and
final authority, in its sole discretion:  (i) to determine the number of shares
subject to each option; (ii) to determine the time or times at which options
will be granted; (iii) to determine the conditions on which options will be
granted or may be exercised; (iv) to determine the option price for the shares
subject to each option, which price shall be subject to the applicable
requirements, if any, of Section 5.1(c) hereof; and (v) to determine the time or
times when each option shall become exercisable and the duration of the exercise
period, which shall not exceed the limitations specified in Section 5.1(a).

   No member of the committee serving as Plan Administrator shall be liable for
any action or determination made in good faith with respect to the Plan or any
option granted thereunder.

   2.3.  Appointment and Proceedings of Committee.  The Board may, from time to
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time, appoint members of the committee serving as Plan Administrator in
substitution for, or in addition to, members previously appointed and may fill
vacancies, however caused, in such committee; provided, however, that each such
appointee will be an Outside Director, as described in Section 2.2.  The
committee serving as Plan Administrator shall hold its meetings at such times
and places as it shall deem advisable.  A majority of its members shall
constitute a quorum, and all actions of such committee shall require the
affirmative vote of a majority of its members.  Any action may be taken by a
written instrument signed by all of the members, and any action so taken shall
be as fully effective as if it had been taken by a vote of a majority of the
members at a meeting duly called and held.


                                      -2-

 
SECTION 3. STOCK

   3.1.  Shares Subject to Plan.  The stock subject to the options granted under
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the Plan shall be shares of the Company's authorized but unissued common stock,
par value $.01 per share ("Common Stock"), or shares of the Company's Common
Stock held in treasury.  The total number of shares that may be issued pursuant
to options granted under the Plan shall not exceed an aggregate of 1,000,000
shares of Common Stock.  Such number of shares shall be subject to adjustment as
provided in Section 7 hereof.

   3.2.  Lapsed or Unexercised Options.  Whenever any outstanding option under
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the Plan expires, is cancelled or is otherwise terminated (other than by
exercise), the shares of Common Stock allocable to the unexercised portion of
such option shall be restored to the Plan and shall again become available for
the grant of other options under the Plan.

   3.3.  Limitation on Grants.  In no event may any Plan participant be granted
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options with respect to more than 500,000 shares of Common Stock in any fiscal
year.  The number of shares of Common Stock issuable pursuant to an option
granted to a Plan participant in a fiscal year that is subsequently forfeited,
cancelled or otherwise terminated shall continue to count toward the foregoing
limitation in such fiscal year.  In addition, if the exercise price of an option
is subsequently reduced, the transaction shall be deemed a cancellation of the
original option and the grant of a new one so that both transactions shall count
toward the maximum shares issuable in the fiscal year of each respective
transaction.

SECTION 4. ELIGIBILITY

   4.1.  Eligible Optionees.  Incentive Options may be granted only to officers
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and other employees of the Company or its Subsidiaries, including members of the
Board who are also employees of the Company or a Subsidiary.  Non-Qualified
Options may be granted to officers or other employees of the Company or its
Subsidiaries, to members of the Board or the board of directors of any
Subsidiary whether or not employees of the Company or such Subsidiary, and to
consultants and other individuals providing services to the Company or its
Subsidiaries.

   4.2.  Limitations on 10% Stockholders.  No Incentive Option shall be granted
         -------------------------------                                       
to an individual who, at the time the Incentive Option is granted, owns
(including ownership attributed pursuant to Section 424(d) of the Code) more
than 10% of the total combined voting power of all classes of stock of the
Company or any parent or Subsidiary of the Company (a "greater-than-10%
stockholder"), unless such Incentive Option provides that (i) the purchase price
per share shall not be less than 110% of the fair market value of the Common
Stock at the time such Incentive Option is granted, and (ii) that such Incentive
Option shall not be exercisable to any extent after the expiration of five years
from the date on which it is granted.

   4.3.  Limitation on Exercisable Options.  The aggregate fair market value
         ---------------------------------                                  
(determined at the time the Incentive Option is granted) of the Common Stock
with respect to which Incentive Options are exercisable for the first time by
any person during any calendar year under the Plan and under any other option
plan of the Company (or a parent or


                                      -3-

 
subsidiary as defined in Section 424 of the Code) shall not exceed $100,000.
Any option granted in excess of the foregoing limitation shall be specifically
designated as being a Non-Qualified Option.

   4.4.  Option Grants to Directors.  As compensation for services to the
         --------------------------                                      
Company, each Director of the Company who is not an employee of the Company (an
"Outside Director") and who (a) is a member of the Board immediately after the
closing of the Company's initial public offering and at the time of such closing
holds no outstanding stock option granted to such Director in his or her
capacity as a Director (a "Prior Option") or (b) is elected to the Board after
the closing of the Company's initial public offering shall automatically be
granted, immediately after the closing of the Company's public offering or upon
his or her initial election, as the case may be, a Non-Qualified Option (an
"Initial Option") to purchase 20,000 shares of Common Stock of the Company,
vesting in equal installments on the first three anniversaries of the date of
grant (provided that the Optionee is then a Director of the Company).  In
addition, immediately following each annual meeting of stockholders of the
Company or special meeting in lieu thereof, there shall automatically be granted
to each Outside Director reelected at or remaining in office after such meeting
a fully-vested Non-Qualified Option to purchase 4,000 shares of Common Stock;
provided that no such automatic grant shall be made to any Outside Director who
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at the time of such meeting holds any outstanding Initial Option or Prior Option
that is not fully vested, unless at least two annual meetings of stockholders of
the Company or special meetings in lieu thereof have intervened between the
closing of the Company's initial public offering (or, if later, the date of the
initial election of such Outside Director) and the meeting following which such
automatic grant would occur.  Each Non-Qualified Option granted to an Outside
Director pursuant to this Section 4.4 shall expire on the tenth anniversary of
the date of grant.  The exercise price of each Non-Qualified Option granted
pursuant to this Section 4.4 shall be equal to the fair market value of the
Common Stock on the date the Non-Qualified Option is granted, such fair market
value to be determined in accordance with the provisions of Section 5.1(c).

SECTION 5. TERMS OF THE OPTION AGREEMENTS

   5.1.   Mandatory Terms.  Each option agreement shall contain such provisions
          ---------------                                                      
as the Plan Administrator shall from time to time deem appropriate.  Option
agreements need not be identical, but each option agreement by appropriate
language shall include the substance of all of the following provisions:

      (a) Expiration.  Notwithstanding any other provision of the Plan or of any
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option agreement, each option shall expire on the date specified in the option
agreement, which date shall not be later than the tenth anniversary of the date
on which the option was granted (fifth anniversary in the case of an Incentive
Option granted to a greater-than-10% stockholder).

      (b) Exercise.  Each option shall be exercisable in full or in installments
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(which need not be equal) and at such times as designated by the Plan
Administrator.  To the extent not exercised, installments shall accumulate and
be exercisable, in whole or in part, at any time after becoming exercisable, but
not later than the date the option expires.


                                      -4-

 
      (c) Purchase Price.  The purchase price per share of the Common Stock
          --------------                                                   
under each Incentive Option shall be not less than the fair market value of the
Common Stock on the date the option is granted (110% of the fair market value in
the case of a greater-than-10% stockholder).  The price at which shares may be
purchased pursuant to Non-Qualified Options shall be specified by the Plan
Administrator at the time the option is granted, and may be equal to or greater
than the fair market value of the shares of Common Stock on the date such Non-
Qualified Option is granted, but shall not be less than the par value of shares
of Common Stock.  For the purpose of the Plan, the fair market value of the
Common Stock shall be the closing price per share on the date of grant of the
option as reported by a nationally recognized stock exchange, or, if the Common
Stock is not listed on such an exchange, as reported by the National Association
of Securities Dealers Automated Quotation System, Inc. ("Nasdaq"), or, if the
Common Stock is not quoted on Nasdaq, the fair market value as determined by the
Plan Administrator.

      (d) Transferability of Options.  Options granted under the Plan and the
          --------------------------                                         
rights and privileges conferred thereby may not be transferred, assigned,
pledged or hypothecated in any manner (whether by operation of law or otherwise)
other than by will or by applicable laws of descent and distribution, and shall
not be subject to execution, attachment or similar process.  Upon any attempt so
to transfer, assign, pledge, hypothecate or otherwise dispose of any option
under the Plan or any right or privilege conferred hereby, contrary to the
provisions of the Plan, or upon the sale or levy or any attachment or similar
process upon the rights and privileges conferred hereby, such option shall
thereupon terminate and become null and void.

      (e) Termination of Employment or Disability or Death of Optionee.  Except
          ------------------------------------------------------------         
as may be otherwise expressly provided in the terms and conditions of the option
granted to an Optionee:

           (i) Options granted hereunder shall terminate on the earliest to
occur of:

               (A) the date of expiration thereof;

               (B) thirty days after the date of termination of the Optionee's
employment with or performance of services for the Company (other than as a
result of death or permanent and total disability of the Optionee), including
upon the Optionee's retirement; or

               (C) twelve months after the date of termination of the Optionee's
employment with or performance of services for the Company as a result of the
death or permanent and total disability of an Optionee under the then
established rules of the Company.

          (ii)  In the event of the termination of an Optionee's employment with
or performance of services for the Company by the Company (other than as a
result of death or permanent and total disability of the Optionee) or upon the
Optionee's retirement, the Optionee's option shall be exercisable during the
thirty-day post-termination period described in Paragraph 5.1(e)(i)(B) to the
extent that it was exercisable at the time of such termination

                                      -5-

 
of employment or performance of services. In the event of the termination of the
Optionee's employment with or performance of services for the Company as a
result of the permanent and total disability of an Optionee, the Optionee's
option shall be exercisable during the twelve-month post-termination period
referred to in Paragraph 5.1(e)(i)(C) to the extent that it was exercisable at
the time of such termination of employment or performance of services. In the
event of the termination of the Optionee's employment with or performance of
services for the Company as a result of the death of the Optionee, the
Optionee's executor, administrator or any person or persons to whom his option
may be transferred by will or by laws of descent and distribution shall have the
right at any time during the twelve-month post-termination period referred to in
Paragraph 5.1(e)(i)(C) to exercise such option, to the extent the Optionee was
entitled to exercise such option at the time of such termination of employment
or performance of services. Should such termination for reason of permanent
disability or death occur after the first anniversary of the date at which the
Optionee was first employed or otherwise began to serve the Company, then at the
Board's discretion, the Option may be exercised for up to the greater of (A) 50%
of all Option shares (and such shares shall be deemed vested) or (B) the number
of shares that had vested as of the date of such death or such retirement. After
the death of the Optionee, his executors, administrators or any person or
persons to whom his Option may be transferred by will or by the laws of descent
and distribution, shall have the right to exercise the Option.

          (iii)   An employment or consulting relationship between the Company
and the Optionee shall be deemed to exist during any period in which the
Optionee is employed in any capacity by the Company or by any Subsidiary or
providing services to the Company, as the case may be. Whether authorized leave
of absence or absence on military or government service shall constitute
termination of the employment relationship between the Company and the Optionee
shall be determined by the Plan Administrator at the time thereof.

      (f) Rights of Optionees.  No Optionee shall be deemed for any purpose to
          -------------------                                                 
be the owner of any shares of Common Stock subject to any option unless and
until (i) the option shall have been exercised with respect to such shares
pursuant to the terms thereof, and (ii) the Company shall have issued and
delivered a certificate representing such shares.  Thereupon, the Optionee shall
have full voting, dividend and other ownership rights with respect to such
shares of Common Stock.

   5.2.   Certain Optional Terms.  The Plan Administrator may in its discretion
          ----------------------                                               
provide, upon the grant of any option hereunder, that the Company shall have an
option to repurchase all or any number of shares purchased upon exercise of such
option.  The repurchase price per share payable by the Company shall be such
amount or be determined by such formula as is fixed by the Plan Administrator at
the time the option for the shares subject to repurchase was granted.  The Plan
Administrator may also provide that the Company shall have a right of first
refusal with respect to the transfer or proposed transfer of any shares
purchased upon exercise of an option granted hereunder.  In the event the Plan
Administrator shall grant options subject to the Company's repurchase rights or
rights of first refusal, the certificate or certificates representing the shares
purchased pursuant to the exercise of such option shall carry a legend
satisfactory to counsel for the Company referring to such rights.


                                      -6-

 
SECTION 6. METHOD OF EXERCISE; PAYMENT OF PURCHASE PRICE

   6.1.  Notice of Exercise.  Any option granted under the Plan may be exercised
         ------------------                                                     
by the Optionee by delivering to the Company on any business day a written
notice specifying the number of shares of Common Stock the Optionee then desires
to purchase and specifying the address to which the certificates for such shares
are to be mailed, accompanied by payment for such shares.

   6.2.  Means of Payment and Delivery.  Common Stock purchased on exercise of
         -----------------------------                                        
an option must be paid for as follows:  (a) in cash or by check (acceptable to
the Company in accordance with guidelines established for this purpose), bank
draft or money order payable to the order of the Company, or (b) through the
delivery of shares of Common Stock (which in the case of shares acquired from
the Company upon exercise of an option, have been outstanding for at least six
months) having a fair market value on the last business day preceding the date
of exercise equal to the purchase price, or (c) by delivery of an unconditional
and irrevocable undertaking by a broker to deliver promptly to the Company
sufficient funds to pay the exercise price, or (d) if so permitted by the
instrument evidencing the option (or in the case of a Non-Qualified Option, by
the Plan Administrator on or after grant of the option), by delivery of a
promissory note of the Optionee to the Company, payable on such terms as are
specified by the Plan Administrator, or (e) by any combination of the
permissible forms of payment; provided, that if the Common Stock delivered upon
                              --------                                         
exercise of the option is an original issue of authorized Common Stock, at least
so much of the exercise price as represents the par value of such Common Stock
must be paid other than by the Optionee's promissory note or personal check.  In
the event that payment of the option price is made under (b) above, the Plan
Administrator may provide that the Optionee be granted an additional option
covering the numbers of shares surrendered, at an exercise price equal to the
fair market value of a share of Common Stock on the date of surrender. For the
purpose of this Section, the fair market value of the shares of Common Stock so
delivered to the Company shall be determined in the manner specified in Section
5.1(c) hereof. As promptly as practicable after receipt of such written
notification and payment, the Company shall deliver to the Optionee certificates
for the number of shares with respect to which such Option has been so
exercised, issued in the Optionee's name; provided, however, that such delivery
shall be deemed effected for all purposes when the Company or a stock transfer
agent of the Company shall have deposited such certificates in the United States
mail, addressed to the Optionee, at the address specified pursuant to Section
6.1.


SECTION 7. ADJUSTMENT UPON CHANGES IN CAPITALIZATION

   7.1  No Effect of Options upon Certain Corporate Transactions.  The existence
        --------------------------------------------------------                
of outstanding options shall not affect in any way the right or power of the
Company or its stockholders to make or authorize any or all adjustments,
recapitalizations, reorganizations or 



                                      -7-

 
other changes in the Company's capital structure or its business, or any merger
or consolidation of the Company, or any issue of Common Stock, or any issue of
bonds, debentures, preferred or prior preference stock ahead of or affecting the
Common Stock or the rights thereof, or the dissolution or liquidation of the
Company, or any sale or transfer of all or any part of its assets or business,
or any other corporate act or proceeding, whether of a similar character or
otherwise.

   7.2. Stock Dividends, Recapitalizations, Etc. If at any time after the
        ---------------------------------------
effective date of the Plan the Company shall effect a subdivision or
consolidation of shares or other capital readjustment, the payment of a stock
dividend, or other increase or reduction of the number of shares of the Common
Stock outstanding, without receiving compensation therefor in money, services or
property, then: (i) the number, class and per share price of shares of stock
subject to outstanding options hereunder, and the number of shares as to which
automatic formula grants of options are to be made under Section 4.4 above,
shall be appropriately adjusted in such a manner as to entitle an Optionee to
receive upon exercise of an option, for the same aggregate cash consideration,
the same total number and class of shares that the owner of an equal number of
outstanding shares of Common Stock would own as a result of the event requiring
the adjustment; and (ii) the number and class of shares with respect to which
options may be granted under the Plan shall be adjusted by substituting for the
total number of shares of Common Stock then reserved for issuance under the Plan
that number and class of shares of stock that the owner of an equal number of
outstanding shares of Common Stock would own as the result of the event
requiring the adjustment.

   7.3.  Determination of Adjustments.  Adjustments under this Section 7 shall
         ----------------------------                                          
be determined by the Plan Administrator and such determinations shall be
conclusive. The Plan Administrator shall have the discretion and power in any
such event to determine and to make effective provision for acceleration of the
time or times at which any option or portion thereof shall become exercisable.
No fractional shares of Common Stock shall be issued under the Plan on account
of any adjustment specified above.

   7.4.  No Adjustment in Certain Cases.  Except as hereinbefore expressly
         ------------------------------                                   
provided, the issue by the Company of shares of stock of any class, or
securities convertible into shares of stock of any class, for cash or property
or for labor or services, either upon direct sale or upon the exercise of rights
or warrants to subscribe therefor, or upon conversion of shares or obligations
of the Company convertible into such shares or other securities, shall not
affect, and no adjustment by reason thereof shall be made with respect to, the
number or price of shares of Common Stock then subject to outstanding options.

SECTION 8. EFFECT OF CERTAIN TRANSACTIONS

   If the Company is a party to a reorganization or merger with one or more
other corporations, whether or not the Company is the surviving or resulting
corporation, or if the Company consolidates with or into one or more other
corporations, or if the Company is liquidated or sells or otherwise disposes of
substantially all of its assets to another corporation (each hereinafter
referred to as a "Transaction"), in any such event while unexercised options
remain outstanding under the Plan, then: (i) subject to the provisions of clause
(iii) below, after the effective date of such Transaction unexercised options
shall remain outstanding and shall be exercisable in shares of Common Stock, or,
if applicable, 


                                      -8-

 
shares of such stock or other securities, cash or property as the holders of
shares of Common Stock received pursuant to the terms of such Transaction; (ii)
the Plan Administrator may accelerate the time for exercise of all unexercised
and unexpired options to and after a date prior to the effective date of such
Transaction; or (iii) any outstanding options may be cancelled by the Plan
Administrator as of the effective date of such Transaction, provided that: (x)
notice of such cancellation shall be given to each holder of an option; (y) the
Plan Administrator shall have accelerated the time for exercise of all
unexercised and unexpired options that it proposes to cancel; and (z) each
holder of an option shall have the right to exercise such option in full.

SECTION 9. AMENDMENT OR TERMINATION OF THE PLAN

   The Board may terminate the Plan at any time, and may amend the Plan at any
time and from time to time, subject to the limitation that, except as provided
in Sections 7 and 8 hereof, no amendment shall be effective unless approved by
the stockholders of the Company in accordance with applicable law and
regulations, at an annual or special meeting held within twelve months before or
after the date of adoption of such amendment, in any instance in which such
amendment would:  (i) increase the number of shares of Common Stock as to which
options may be granted under the Plan; or (ii) change in substance the
provisions of Section 4 hereof relating to eligibility to participate in the
Plan. 

   Except as provided in Sections 7 and 8 hereof, rights and obligations under
any option granted before termination or amendment of the Plan shall not be
altered or impaired by such termination or amendment except with the consent of
the Optionee,

SECTION 10.  NON-EXCLUSIVITY OF THE PLAN; NON-UNIFORM DETERMINATIONS

   Neither the adoption of the Plan by the Board nor the approval of the Plan by
the stockholders of the Company shall be construed as creating any limitations
on the power of the Board to adopt such other incentive arrangements as it may
deem desirable, including without limitation the granting of stock options
otherwise than under the Plan, and such arrangements may be either applicable
generally or only in specific cases.

   The Plan Administrator's determinations under the Plan need not be uniform
and may be made by it selectively among persons who receive or are eligible to
receive options under the Plan (whether or not such persons are similarly
situated).  Without limiting the generality of the foregoing, the Plan
Administrator shall be entitled, among other things, to make non-uniform and
selective determinations, and to enter into non-uniform and selective option
agreements, as to (i) the persons to receive options under the Plan, (ii) the
terms and provisions of options, (iii) the exercise by the Plan Administrator of
its discretion in respect of the exercise of options pursuant to the terms of
the Plan, and (iv) the treatment of leaves of absence pursuant to Section 5.1(e)
hereof.


                                      -9-

 
SECTION 11.  GOVERNMENT AND OTHER REGULATIONS; GOVERNING LAW; WITHHOLDING TAXES

   The obligation of the Company to sell and deliver shares of Common Stock with
respect to options granted under the Plan shall be subject to all applicable
laws, rules and regulations, including all applicable federal and state
securities laws, and the obtaining of all such approvals by government agencies
as may be deemed necessary or appropriate by the Plan Administrator.  All shares
sold under the Plan shall bear appropriate legends.  The Company may, but shall
in no event be obligated to, register or qualify any shares covered by options
under applicable federal and state securities laws; and in the event that any
shares are so registered or qualified the Company may remove any legend on
certificates representing such shares.  The Company shall not be obligated to
take any other affirmative action in order to cause the exercise of an option or
the issuance of shares pursuant thereto to comply with any law or regulation of
any governmental authority.  The Plan shall be governed by and construed in
accordance with the laws of The Commonwealth of Massachusetts.

   Whenever under the Plan shares are to be delivered upon exercise of an
option, the Company shall be entitled to require as a condition of delivery that
the Optionee remit an amount sufficient to satisfy all federal, state and other
governmental withholding tax requirements related thereto. An employee may elect
to have such tax withholding obligation satisfied, in whole or in part, by: (i)
authorizing the Company to withhold from shares of Common Stock to be issued
pursuant to the exercise of a Non-Qualified Option a number of shares with an
aggregate fair market value (as defined in Section 5.1(c) hereof determined as
of the date the withholding is effected) that would satisfy the withholding
amount due with respect to such exercise; or (ii) transferring to the Company
shares of Common Stock owned by the employee with an aggregate fair market value
(as defined in Section 5.1(c) hereof determined as of the date the withholding
is effected) that would satisfy the withholding amount due. 


                                     -10-

 
SECTION 12.  "LOCKUP" AGREEMENT

   The Plan Administrator may in its discretion specify upon granting an option
that the Optionee shall agree, for a period of time (not to exceed 180 days)
from the effective date of any registration of securities of the Company, upon
request of the Company or the underwriter or underwriters managing any
underwritten offering of the Company's securities, not to sell, make any short
sale of, loan, grant any option for the purchase of, or otherwise dispose of any
shares issued pursuant to the exercise of such option, without the prior written
consent of the Company or such underwriter or underwriters, as the case may be.

SECTION 13.  EFFECTIVE DATE AND DURATION OF PLAN

   The Plan shall become effective upon the closing of the Company's initial
public offering of shares of Common Stock provided that the stockholders of the
Company shall have approved the Plan within twelve months prior to or following
the adoption of the Plan by the Board. No option may be granted under the Plan
after the tenth anniversary of the effective date. The Plan shall terminate (i)
when the total amount of the Stock with respect to which options may be granted
shall have been issued upon the exercise of options or (ii) by action of the
Board pursuant to Section 9 hereof, whichever shall first occur.


                                     -11-