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                                                                   EXHIBIT 10.10
                                                                   -------------
                           OPNET Technologies, Inc.

             Amended and Restated 1993 Incentive Stock Option Plan

                                   ARTICLE I
                                    GENERAL

1.01.     Purpose.

             The purposes of this Amended and Restated 1993 Incentive Stock
Option Plan (the "Plan") are to: (1) closely associate the interest of the
employees of OPNET Technologies, Inc. ("OPNET"), and its subsidiaries and
affiliates (sometimes collectively referred hereafter to as the "Company"), with
OPNET's shareholders by providing employees with an equity ownership in OPNET;
(2) maintain competitive compensation levels; and (3) attract, motivate and
provide an incentive to employees for continuous employment with the Company.

1.02.     Administration.

               (a) Administration by Board of Directors. The Plan will be
          administered by the Board of Directors of OPNET (the "Board"). The
          Board shall have authority to designate the employees or class of
          employees eligible to participate in the Plan, to grant Incentive
          Stock Options (as defined below) and to adopt, amend and repeal such
          administrative rules, guidelines and practices relating to the Plan as
          it shall deem advisable. The Board may correct any defect, supply any
          omission or reconcile any inconsistency in the Plan or any Incentive
          Stock Option in the manner and to the extent it shall deem expedient
          to carry the Plan into effect and it shall be the sole and final judge
          of such expediency. All decisions by the Board shall be made in the
          Board's sole discretion and shall be final and binding on all persons
          having or claiming any interest in the Plan or in any Incentive Stock
          Option. No director or person acting pursuant to the authority
          delegated by the Board shall be liable for any action or determination
          relating to or under the Plan made in good faith.

               (b) Appointment of Committees. To the extent permitted by
          applicable law, the Board may delegate any or all of its powers under
          the Plan to one or more committees or subcommittees of the Board (a
          "Committee"). All references in the Plan to the "Board" shall mean the
          Board or a Committee of the Board to the extent that the Board's
          powers or authority under the Plan have been delegated to such
          Committee.

1.03.     Eligibility for Participation.

          Participants in the Plan shall be selected by the Board from the
executive officers and other key employees of the Company who occupy responsible
managerial or professional positions and who have the capability of making a
substantial contribution to the success of the Company. In making this selection
and determining the form and amount of awards, the Board shall consider any
factors deemed relevant, including the individual's functions, responsibilities,
value of services to the Company, and past and potential contributions to the
Company's

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profitability and sound growth.

1.04.     Type of Awards Under Plan.

          Awards under the Plan shall be in the form of Incentive Stock Options,
as described in Article II.

1.05.     Aggregate Limitation on Awards.

               (a) Shares of stock that may be issued under the Plan shall be
          authorized and unissued or treasury shares of Common Stock, par value
          $.001 of OPNET ("Common Stock"). The maximum number of shares of
          Common Stock that may be issued under the Plan shall be 2,000,000,
          subject to adjustment under Section 4.08.

               (b) For purposes of calculating the maximum number of shares of
          Common Stock that may be issued under the Plan:

                       (i)     All the shares issued (including the shares, if
                  any, withheld for tax-withholding requirements) shall be
                  counted when cash is used as full payment for shares issued
                  upon exercise of an Incentive Stock Option;

                       (ii)    Only the net shares of Common Stock issued
                  (including the shares, if any, withheld for tax withholding
                  requirements) shall be counted when shares of Common Stock are
                  used as full or partial payment for shares issued upon
                  exercise of an Incentive Stock Option.

               (c) Shares of Common Stock tendered by a participant as payment
          for shares of Common Stock issued upon exercise of an Incentive Stock
          Option shall be available for issuance under the Plan. Any shares of
          Common Stock subject to an Incentive Stock Option which for any reason
          is terminated, unexercised or expires shall again be available for
          issuance under the Plan.

1.06.    Effective Date and Term of Plan.

               (a) The Plan became effective on March 31, 1993, the date on
which it was adopted by the Board.

               (b) No awards shall be made under the Plan after the last day of
OPNET's fiscal year ending March 31, 2003, provided, however, that the Plan and
all awards made under the Plan prior to such date shall remain in effect until
such awards have been satisfied or terminated in accordance with the Plan and
the terms of such awards.

                                  ARTICLE II
                            INCENTIVE STOCK OPTIONS

2.01.    Award of Incentive Stock Options.

        The Board may, from time to time, on such terms and conditions as the
Board may prescribe, subject to the provisions of the Plan, grant to any
participant in the Plan one or more

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"incentive stock options," intended to qualify as such under the provisions of
Section 422 of the Internal Revenue Code of 1986, as amended ("Incentive Stock
Options"), to purchase for cash or shares the number of shares of Common Stock
allotted by the Board. The date an Incentive Stock Option is granted shall mean
the date selected by the Board as of which the Board allots a specific number of
shares to a participant for purchase pursuant to the Plan.

2.02.     Incentive Stock Option Agreements.

          The grant of an Incentive Stock Option shall be evidenced by a written
Incentive Stock Option Agreement executed by OPNET and the holder of an
Incentive Stock Option (the "Optionee") stating the number of shares of Common
Stock subject to the Incentive Stock Option evidenced thereby, and in such form
as the Board may from time to time determine.

2.03.     Option Exercise Price.

          The option exercise price per share of Common Stock deliverable upon
the exercise of an Incentive Stock Option shall be 100% of the fair market value
of a share of Common Stock on the date the Incentive Stock Option is granted for
those Optionees who own less than 10% of the Common Stock of OPNET or any
subsidiary or parent corporation, and 110% of such fair market value for those
Optionees who own 10% or more of the Common Stock of OPNET or any subsidiary or
parent corporation.

2.04.     Term and Exercise.

          Each Incentive Stock Option shall be fully exercisable within such
period after the date of its grant as the Board determines and, unless a shorter
period is provided by the Board or another Section of this Plan, may be
exercised during a period of ten years from the date of grant thereof (the
"Option Term"), provided that for any Optionee who owns 10% or more of the
Common Stock of OPNET or any of its subsidiary or parent corporations, the
Option Term shall expire not later than five years from the date of grant of an
Incentive Stock Option. No Incentive Stock Option shall be exercisable after the
expiration of its Option Term.

2.05.     Manner of Payment.

          Each Incentive Stock Option Agreement shall set forth the procedure
governing the exercise of the Incentive Stock Options granted thereunder, and
shall provide that, upon such exercise in respect of any shares of Common Stock
subject thereto, the optionee shall pay to OPNET, in full, the option exercise
price for such shares with cash or with previously owned shares of Common Stock.

2.06.     Rights as Shareholders.

          As soon as practicable after receipt of payment, OPNET shall deliver
to the Optionee a certificate or certificates for such shares of Common Stock.
The recipient of any award under the Plan shall have no rights as a shareholder
with respect thereto unless and until certificates for shares of Common Stock
are issued to him. The Optionee shall become a shareholder of OPNET with respect
to Common Stock represented by share certificates so issued and as such shall be
fully entitled to receive dividends if and when declared, to vote, and to
exercise all other rights of a shareholder.

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2.07.     Maximum Amount of Incentive Stock Option Grant.

          The aggregate fair market value (determined on the date the option is
granted) of Common Stock subject to an Incentive Stock Option granted to any
Optionee by the Board in any calendar year shall not exceed $100,000.

2.08.     Death of Optionee.

               (a) Upon the death of an Optionee, any Incentive Stock Option
          exercisable on the date of death may be exercised by the Optionee's
          estate or by a person who acquires the right to exercise such
          Incentive Stock Option by bequest or inheritance or by reason of the
          death of the Optionee, provided that such exercise occurs within both
          the remaining option term of the Incentive Stock Option and one year
          after the Optionee's death.

               (b) The provisions of this Section shall apply notwithstanding
          the fact that the Optionee's employment may have terminated prior to
          death, but only to the extent of any Incentive Stock Options
          exercisable on the date of death.

2.09.     Retirement or Disability.

          Upon the termination of the Optionee's employment by reason of
permanent disability or retirement (as each is determined by the Board), the
Optionee may, within 36 months from the date of such termination of employment,
exercise any Incentive Stock Options to the extent such Incentive Stock Options
were exercisable at the date of such termination of employment. Notwithstanding
the foregoing, the tax treatment available pursuant to Section 422 of the
Internal Revenue Code of 1986 upon the exercise of an Incentive Stock Option
will not be available to an Optionee who exercises any Incentive Stock Options
more than:

                    (i)   one year after the date of termination of employment
              due to permanent disability, as defined in Section 22(e)(8) of the
              Code; or

                    (ii)  three months after the date of termination of
              employment due to retirement.

2.10.     Termination for Other Reasons.

          Except as provided in Sections 2.08, 2.09 and 4.08 or except as
otherwise determined by the Board, all Incentive Stock Options shall terminate
upon the termination of an Optionee's employment.

                                  ARTICLE III
                              CERTAIN RESTRICTIONS

3.01.    General Restrictions.

               (a) No award under the Plan may be consummated in whole or in
         part if at any time the Board shall determine that such award requires
         the:

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                       (i)   listing, registration or qualification of the
                  shares of Common Stock subject or related thereto upon any
                  securities exchange or under any state or Federal law, or

                       (ii)  consent or approval of any government regulatory
                  body, or

                       (iii) agreement by the grantee of the award with respect
                  to the disposition of shares of Common Stock as a condition
                  of, or in connection with, the granting of such award or the
                  issue or purchase of shares of Common Stock thereunder.

               (b) Awards under the Plan shall be consummated when the Board
          determines that such listing, registration, qualification, consent,
          approval or agreement contemplated in Section 3.01(a) shall have been
          effected or obtained on the terms and any conditions acceptable to the
          Board.

3.02.     Transfer Restrictions.

          Notwithstanding anything to the contrary herein, no shares of Common
Stock acquired upon exercise of an Option under the Plan may be sold,
transferred, assigned or otherwise disposed of, unless the holder of such shares
has first obtained the written approval of the Board.

3.03.     Repurchase.

          Notwithstanding anything to the contrary set forth herein, OPNET shall
have the right to purchase shares of Common Stock acquired pursuant to any
exercise of Options under this Plan for a period of twelve (12) months after the
Optionee's employment with the Company has terminated for any reason, at a price
per share equal to the fair market value thereof as most recently determined by
the Board.

3.04.     Legend.

          Each certificate evidencing the Common Stock issued upon exercise of
Options under the Plan shall bear the following legend:

               The shares of Common Stock represented by this certificate have
               not been registered under the Securities Act of 1933, as amended,
               or any state securities law, and may not be transferred or sold
               unless they are so registered or are offered and sold in a
               transaction that, in the opinion of counsel acceptable to OPNET,
               does not require registration. The transfer of Common Stock
               represented by this certificate is restricted under the terms of
               the Amended and Restated 1993 Incentive Stock Option Plan adopted
               by OPNET Technologies, Inc., a copy of which is on file and
               available for inspection at the registered office of the Company.
               No transfer or sale of this Common Stock shall be effective
               unless such transfer, in the opinion of legal counsel for the
               Company, is made in accordance with the terms of said Plan.

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                                  ARTICLE IV
                                 MISCELLANEOUS

4.01.     Non-Assignability.

          No award under the Plan shall be assignable or transferable by the
recipient thereof except by will or by the laws of descent and distribution.
During the life of the recipient, such award shall be exercisable only by such
person or by such person's guardian or legal representative.

4.02.    Withholding Taxes.

        Whenever OPNET proposes or is required to issue or transfer shares of
Common Stock under the Plan, OPNET shall have the right to require the grantee
to remit to OPNET an amount sufficient to satisfy any Federal, state, and/or
local withholding tax requirements prior to the delivery of any certificate or
certificates for such shares. Alternatively, OPNET may issue or transfer such
shares of Common Stock, net of the number of shares sufficient to satisfy the
withholding tax requirements. For withholding tax purposes, the shares of Common
Stock shall be valued on the date the withholding obligation is incurred.

4.03.     Right to Terminate Employment.

          Nothing in the Plan or in any agreement entered into pursuant to the
Plan shall confer upon any participant the right to continue in the employment
of the Company or affect any right that the Company may have to terminate the
employment of such participant.

4.04.     Non-Uniform Determinations.

          The Board's determinations under the Plan (including, without
limitation, determinations of the persons to receive awards; the form, amount,
and timing of such awards; the terms and provisions of such awards; and the
agreements evidencing same) need not be uniform and may be made by it
selectively among persons who receive, or are eligible to receive, awards under
the Plan, whether or not such persons are similarly situated.

4.05.     Definitions.

          In this Plan the following definitions shall apply:

               (a) "Affiliate" means any person or entity which directly, or
          indirectly through one or more intermediaries, controls, is controlled
          by, or is under common control with OPNET.

               (b) "Fair market value" as of any date and in respect of any
          shares of Common Stock means the fair market value of the shares of
          Common Stock as most recently determined in good faith by the Board in
          such manner as it may deem appropriate. The Board may rely upon
          independent expert advice and/or such other and further advice as it
          may deem appropriate and, in its discretion, from time to time select.
          In no event shall the fair market value of any share of Common Stock
          be less than its par value.

               (c) "Option" means Incentive Stock Option.

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               (d) "Option price" or "Option exercise price" means the purchase
          price per share of Common Stock deliverable upon the exercise of an
          Option.

               (e) "Subsidiary" means any corporation of which, at the time,
          more than 50% of the shares entitled to vote generally in an election
          of directors are owned directly or indirectly by OPNET or any
          subsidiary thereof.

4.06.     Leaves of Absence.

          The Board shall be entitled to make such rules, regulations and
determinations as it deems appropriate under the Plan in respect of any leave of
absence taken by the recipient of any award. Without limiting the generality of
the foregoing, the Board shall be entitled to determine:

                        (i)    whether or not any such leave of absence shall
                 constitute a termination of employment within the meaning of
                 the Plan; and

                        (ii)   the impact, if any, of any such leave of absence
                 on awards under the Plan theretofore made to any recipient who
                 takes such a leave of absence.

4.07.     Newly Eligible Employees.

          The Board shall be entitled to make such rules, regulations,
determinations and awards as it deems appropriate in respect of any employee who
becomes eligible to participate in the Plan or any portion thereof after the
commencement of an award or incentive period.

4.08.     Adjustments for Changes in Common Stock and Certain Other Events.

               (a) Changes in Capitalization. In the event of any stock split,
          reverse stock split, stock dividend, recapitalization, combination of
          shares, reclassification of shares, spin-off or other similar change
          in capitalization or event, or any distribution to holders of Common
          Stock, other than a normal cash dividend, (i) the number and class of
          securities available under the Plan and (ii) the number and class of
          securities and exercise price per share subject to each outstanding
          Incentive Stock Option shall be appropriately adjusted by OPNET (or
          substituted Incentive Stock Options may be made, if applicable) to the
          extent the Board shall determine, in good faith, that such an
          adjustment (or substitution) is necessary and appropriate. If this
          Section 4.08(a) applies and Section 4.08(c) also applies to any event,
          Section 4.08(c) shall be applicable to such event, and this Section
          4.08(a) shall not be applicable.

               (b) Liquidation or Dissolution. In the event of a proposed
          liquidation or dissolution of OPNET, the Board shall upon written
          notice to the participants provide that all then unexercised Incentive
          Stock Options will (i) become exercisable in full as of a specified
          time at least 10 business days prior to the effective date of such
          liquidation or dissolution and (ii) terminate effective upon such
          liquidation or dissolution, except to the extent exercised before such
          effective date.

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               (c) Acquisition and Change in Control Events

                   (1) Definitions

                         (A) An "Acquisition Event" shall mean:

                              (i)     any merger or consolidation of OPNET with
                                      or into another entity as a result of
                                      which the Common Stock is converted into
                                      or exchanged for the right to receive
                                      cash, securities or other property; or

                              (ii)    any exchange of shares of OPNET for cash,
                                      securities or other property pursuant to a
                                      statutory share exchange transaction.

                         (B) A "Change in Control Event" shall mean:

                              (i)     the acquisition by an individual, entity
                                      or group (within the meaning of Section
                                      13(d)(3) or 14(d)(2) of the Securities
                                      Exchange Act of 1934, as amended (the
                                      "Exchange Act") (a "Person") of beneficial
                                      ownership of any capital stock of OPNET
                                      if, after such acquisition, such Person
                                      beneficially owns (within the meaning of
                                      Rule 13d-3 promulgated under the Exchange
                                      Act) more than 30% of either (x) the then-
                                      outstanding shares of Common Stock of
                                      OPNET (the "Outstanding Company Common
                                      Stock") or (y) the combined voting power
                                      of the then-outstanding securities of
                                      OPNET entitled to vote generally in the
                                      election of directors (the "Outstanding
                                      Company Voting Securities"); provided,
                                                                   --------
                                      however, that for purposes of this
                                      -------
                                      subsection (i), the following acquisitions
                                      shall not constitute a Change in Control
                                      Event: (A) any acquisition directly from
                                      OPNET (excluding an acquisition pursuant
                                      to the exercise, conversion or exchange of
                                      any security exercisable for, convertible
                                      into or exchangeable for Common Stock or
                                      voting securities of OPNET, unless the
                                      Person exercising, converting or
                                      exchanging such security acquired such
                                      security directly from OPNET or an
                                      underwriter or agent of OPNET), (B) any
                                      acquisition by any employee benefit plan
                                      (or related trust) sponsored or maintained
                                      by

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                                      OPNET or any corporation controlled by
                                      OPNET, (C) any acquisition by any
                                      corporation pursuant to a Business
                                      Combination (as defined below) which
                                      complies with clauses (x) and (y) of
                                      subsection (iii) of this definition or (D)
                                      any acquisition by Marc A. Cohen or Alain
                                      J. Cohen (each such party is referred to
                                      herein as an "Exempt Person") of any
                                      shares of Common Stock;

                              (ii)    such time as the Continuing Directors (as
                                      defined below) do not constitute a
                                      majority of the Board (or, if applicable,
                                      the Board of Directors of a successor
                                      corporation to OPNET), where the term
                                      "Continuing Director" means at any date a
                                      member of the Board (x) who was a member
                                      of the Board on the date of the initial
                                      adoption of this Plan by the Board or (y)
                                      who was nominated or elected subsequent to
                                      such date by at least a majority of the
                                      directors who were Continuing Directors at
                                      the time of such nomination or election or
                                      whose election to the Board was
                                      recommended or endorsed by at least a
                                      majority of the directors who were
                                      Continuing Directors at the time of such
                                      nomination or election; provided, however,
                                                              --------  -------
                                      that there shall be excluded from this
                                      clause (y) any individual whose initial
                                      assumption of office occurred as a result
                                      of an actual or threatened election
                                      contest with respect to the election or
                                      removal of directors or other actual or
                                      threatened solicitation of proxies or
                                      consents, by or on behalf of a person
                                      other than the Board; or

                              (iii)   the consummation of a merger,
                                      consolidation, reorganization,
                                      recapitalization or statutory share
                                      exchange involving OPNET or a sale or
                                      other disposition of all or substantially
                                      all of the assets of OPNET (a "Business
                                      Combination"), unless, immediately
                                      following such Business Combination, each
                                      of the following two conditions is
                                      satisfied: (x) all or substantially all of
                                      the individuals and entities who were the
                                      beneficial owners of the Outstanding
                                      Company Common Stock and Outstanding
                                      Company Voting Securities immediately
                                      prior to such

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                                      Business Combination beneficially own,
                                      directly or indirectly, more than 50% of
                                      the then-outstanding shares of common
                                      stock and the combined voting power of the
                                      then-outstanding securities entitled to
                                      vote generally in the election of
                                      directors, respectively, of the resulting
                                      or acquiring corporation in such Business
                                      Combination (which shall include, without
                                      limitation, a corporation which as a
                                      result of such transaction owns OPNET or
                                      substantially all of OPNET's assets either
                                      directly or through one or more
                                      subsidiaries) (such resulting or acquiring
                                      corporation is referred to herein as the
                                      "Acquiring Corporation") in substantially
                                      the same proportions as their ownership of
                                      the Outstanding Company Common Stock and
                                      Outstanding Company Voting Securities,
                                      respectively, immediately prior to such
                                      Business Combination and (y) no Person
                                      (excluding Exempt Persons, the Acquiring
                                      Corporation or any employee benefit plan
                                      (or related trust) maintained or sponsored
                                      by OPNET or by the Acquiring Corporation)
                                      beneficially owns, directly or indirectly,
                                      30% or more of the then-outstanding shares
                                      of common stock of the Acquiring
                                      Corporation, or of the combined voting
                                      power of the then-outstanding securities
                                      of such corporation entitled to vote
                                      generally in the election of directors
                                      (except to the extent that such ownership
                                      existed prior to the Business
                                      Combination).

                    (C) "Good Reason" shall mean any significant diminution in
                    the participant's title, authority, or responsibilities from
                    and after such Acquisition Event or Change in Control Event,
                    as the case may be, or any reduction in the annual cash
                    compensation payable to the participant from and after such
                    Acquisition Event or Change in Control Event, as the case
                    may be or the relocation of the place of business at which
                    the participant is principally located to a location that is
                    greater than 50 miles from the current site.

                    (D) "Cause" shall mean any (i) willful failure by the
                    participant, which failure is not cured within 30 days of
                    written notice to the participant from OPNET, to perform his
                    or her

                                      -10-
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                    material responsibilities to OPNET or (ii) willful
                    misconduct by the participant which affects the business
                    reputation of OPNET. The participant shall be considered to
                    have been discharged for "Cause" if OPNET determines, within
                    30 days after the participant's resignation, that discharge
                    for Cause was warranted.

            (2)  Effect on Options

                    (A) Acquisition Event. Upon the occurrence of an Acquisition
                    Event (regardless of whether such event also constitutes a
                    Change in Control Event), or the execution by OPNET of any
                    agreement with respect to an Acquisition Event (regardless
                    of whether such event will result in a Change in Control
                    Event), the Board shall provide that all outstanding
                    Incentive Stock Options shall be assumed, or equivalent
                    options shall be substituted for, by the acquiring or
                    succeeding corporation (or an affiliate thereof); provided
                                                                      --------
                    that if such Acquisition Event also constitutes a Change in
                    ----
                    Control Event, except to the extent specifically provided to
                    the contrary in the instrument evidencing any Incentive
                    Stock Option or any other agreement between a participant
                    and OPNET, such assumed or substituted options shall become
                    immediately exercisable in full if, on or prior to the first
                    anniversary of the date of the consummation of the
                    Acquisition Event, the participant's employment with OPNET
                    or the acquiring or succeeding corporation is terminated for
                    Good Reason by the participant or is terminated without
                    Cause by OPNET or the acquiring or succeeding corporation.
                    For purposes hereof, an Incentive Stock Option shall be
                    considered to be assumed if, following consummation of the
                    Acquisition Event, the Incentive Stock Option confers the
                    right to purchase, for each share of Common Stock subject to
                    the Incentive Stock Option immediately prior to the
                    consummation of the Acquisition Event, the consideration
                    (whether cash, securities or other property) received as a
                    result of the Acquisition Event by holders of Common Stock
                    for each share of Common Stock held immediately prior to the
                    consummation of the Acquisition Event (and if holders were
                    offered a choice of consideration, the type of consideration
                    chosen by the holders of a majority of the outstanding
                    shares of Common Stock); provided, however, that if the
                    consideration received as a result of the Acquisition Event
                    is not solely common stock of the acquiring or succeeding
                    corporation (or an affiliate thereof), OPNET may, with the
                    consent of the acquiring or succeeding corporation, provide
                    for the consideration to be received upon the exercise of
                    Options to

                                      -11-
<PAGE>

                    consist solely of common stock of the acquiring
                    or succeeding corporation (or an affiliate thereof)
                    equivalent in fair market value to the per share
                    consideration received by holders of outstanding shares of
                    Common Stock as a result of the Acquisition Event.

                         Notwithstanding the foregoing, if the acquiring or
                    succeeding corporation (or an affiliate thereof) does not
                    agree to assume, or substitute for, such Incentive Stock
                    Options, then the Board shall, upon written notice to the
                    participants, provide that all then unexercised Options will
                    become exercisable in full as of a specified time prior to
                    the Acquisition Event and will terminate immediately prior
                    to the consummation of such Acquisition Event, except to the
                    extent exercised by the participants before the consummation
                    of such Acquisition Event; provided, however, that in the
                    event of an Acquisition Event under the terms of which
                    holders of Common Stock will receive upon consummation
                    thereof a cash payment for each share of Common Stock
                    surrendered pursuant to such Acquisition Event (the
                    "Acquisition Price"), then the Board may instead provide
                    that all outstanding Options shall terminate upon
                    consummation of such Acquisition Event and that each
                    participant shall receive, in exchange therefor, a cash
                    payment equal to the amount (if any) by which (A) the
                    Acquisition Price multiplied by the number of shares of
                    Common Stock subject to such outstanding Incentive Stock
                    Options (whether or not then exercisable) exceeds (B) the
                    aggregate exercise price of such Incentive Stock Options.

                    (B) Change in Control Event that is not an Acquisition
                    Event. Upon the occurrence of a Change in Control Event that
                    does not also constitute an Acquisition Event, except to the
                    extent specifically provided to the contrary in the
                    instrument evidencing any Incentive Stock Option or any
                    other agreement between a participant and OPNET, each such
                    Incentive Stock Option shall be immediately exercisable in
                    full if, on or prior to the first anniversary of the date of
                    the consummation of the Change in Control Event, the
                    participant's employment with OPNET or the acquiring or
                    succeeding corporation is terminated for Good Reason by the
                    participant or is terminated without Cause by OPNET or the
                    acquiring or succeeding corporation.

          (3)  Limitations. Notwithstanding the foregoing provisions of this
               Section 4.08(c), if the Change in Control Event is intended to be
               accounted for as a "pooling of interests" for financial
               accounting purposes,
                                      -12-
<PAGE>

                    and if the acceleration to be effected by the foregoing
                    provisions of this Section 4.08(c) would preclude accounting
                    for the Change in Control Event as a "pooling of interests"
                    for financial accounting purposes, then no such acceleration
                    shall occur upon the Change in Control Event.

4.09.     Amendment of the Plan.

               (a)  The Board may, without further action by the shareholders
          and without receiving further consideration from the participant,
          amend this Plan or condition or modify awards under this Plan in
          response to changes in securities or other laws or rules, regulations
          or regulatory interpretations thereof applicable to this Plan or to
          comply with stock exchange rules or requirements.

               (b)  The Board may at any time and from time to time terminate or
          modify or amend the Plan in any respect, except that without
          shareholder approval the Board may not:

                         (i)   Increase the maximum number of shares of Common
                    Stock that may be issued under the Plan (other than
                    increases pursuant to Section 4.08),

                         (ii)  Extend the period during which any award may be
                    granted or exercised, or

                         (iii) Extend the term of the Plan.


               (c) The termination or any modification or amendment of the Plan,
          except as provided in Section 4.09(a), shall not without the consent
          of a participant affect his or her rights under an award previously
          granted to him or her.

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