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                                                                    Exhibit 10.5


                               ALLAIRE CORPORATION
                            1998 STOCK INCENTIVE PLAN
                        INCENTIVE STOCK OPTION AGREEMENT


     This is an INCENTIVE STOCK OPTION AGREEMENT between Allaire Corporation, a
Delaware corporation (the "Company"), and the optionee (the "Optionee")
identified on the Notice of Grant of Stock Options to which this Agreement is
attached and which is incorporated into this Agreement by reference (the
"Notice").

     WHEREAS, the Company desires to carry out the purposes of the Allaire
Corporation 1998 Stock Incentive Plan (the "Plan") by affording the Optionee an
opportunity to purchase shares of Common Stock of the Company, par value $.01
per share ("Common Stock"), according to the terms set forth herein.

     NOW THEREFORE, the parties hereto hereby agree as follows:

          1. GRANT OF OPTION. Subject to the terms of the Plan, the Company
hereby grants to the Optionee the right and option (the "Option") to purchase
the number of shares of the Company's Common Stock specified in the Notice (the
"Shares") on the terms and conditions hereinafter set forth. Such Option is
intended by the Company and the Optionee to be an Incentive Stock Option as
defined in the Plan.

          2. PURCHASE PRICE. The purchase price of each of the Shares subject to
the Option shall be the exercise price per share specified in the Notice, which
price has been specified in accordance with Section 5(a) of the Plan.

          3. OPTION PERIOD.

          (a) Subject to the provisions of Sections 5 and 6 of this Agreement,
     the Option shall become exercisable as to the number of Shares and on the
     dates specified in the exercise schedule in the Notice. The exercise
     schedule shall be cumulative; thus, to the extent the Option has not
     already been exercised and has not expired, terminated or been canceled,
     the Optionee may at any time, and from time to time, purchase all or any
     portion of the Shares then purchasable under the exercise schedule.

          (b) The Option and all rights to purchase Shares thereunder shall
     cease on the earliest of:

               (i) the expiration date specified in the Notice (which date shall
               not be more than ten years after the date of this Agreement);

               (ii) termination of the Optionee's employment for Cause (as
               defined in the Plan);

               (iii) the expiration of the period after the termination of the
               Optionee's employment, other than a termination for Cause, within
               which the Option is exercisable as specified in Section 5(a) or
               5(b) of this Agreement, whichever is applicable; or

               (iv) the date, if any, fixed for cancellation pursuant to Section
               6(b)(iii) of this Agreement.

Notwithstanding any other provision in this Agreement, in no event may anyone
exercise the Option, in whole or in part, after its original expiration date.

          4. MANNER OF EXERCISING OPTION.

          (a) The Option may be exercised in whole or in part, by delivering
     written notice of exercise to the Company, specifying the number of shares
     to be purchased. Payment of the purchase price may be made by one or more
     of the following methods:

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               (i) in cash, by certified or bank check or other instrument
               acceptable to the committee under the Plan (the "Committee"); or

               (ii) in the form of shares of the Company's Common Stock that are
               not then subject to restrictions, if permitted by the Committee,
               in its discretion. Such surrendered shares shall be valued at
               Fair Market Value (as defined in the Plan) on the exercise date;
               or

               (iii) by the Optionee delivering to the Company a properly
               executed exercise notice together with irrevocable instructions
               to a broker to promptly deliver to the Company cash or a check
               payable and acceptable to the Company to pay the purchase price;
               provided that in the event the Optionee chooses to pay the
               purchase price as so provided, the Optionee and the broker shall
               comply with such procedures and enter into such agreements of
               indemnity and other agreements as the Committee shall prescribe
               as a condition of such payment procedure. The Company need not
               act upon such exercise notice until the Company receives full
               payment of the exercise price; or

               (iv) by any other means, (including, without limitation, by
               delivery of a promissory note of the Optionee, payable on such
               terms as specified by the Committee) which the Committee
               determines are consistent with the purpose of the Plan and with
               applicable laws and regulations.

          (b) The delivery of certificates representing shares of the Company's
     Common Stock to be purchased pursuant to the exercise of the Option will be
     contingent upon receipt by the Company of the full purchase price for such
     shares from the Optionee or the Optionee's legal representative, heirs or
     legatees and the fulfillment of any other requirements contained in the
     Plan or imposed by applicable law.

          5. EXERCISABILITY OF OPTION AFTER TERMINATION OF EMPLOYMENT.

          (a) During the lifetime of the Optionee, the Option may be exercised
     only while the Optionee is employed by the Company or a parent or
     subsidiary thereof, and only if the Optionee has been continuously so
     employed since the date of this Agreement, except that:


               (i) the Option shall continue to be exercisable for three months
               after termination of the Optionee's employment, unless the
               Optionee's employment was terminated for Cause, but only to the
               extent that the Option was exercisable immediately prior to the
               Optionee's termination of employment;

               (ii) in the event the Optionee's employment terminates due to
               Disability, the Optionee or his or her legal representative may
               exercise the Option within one year after the termination of the
               Optionee's employment;

               (iii) in the event the Optionee's employment terminates due to
               Normal Retirement, the Option shall continue to be exercisable
               for three months after the date of such Normal Retirement; and

               (iv) if the Optionee's employment terminates after the Committee
               notifies the Optionee pursuant to Section 6(b)(iii) of this
               Agreement that the Option shall be canceled, the Optionee may
               exercise the Option at any time permitted by Section 6(b)(iii).

          (b) In the event of the Optionee's death prior to expiration of the
     Option, the legal representative, heirs or legatees of the Optionee's
     estate or the personal who acquired the right to exercise the Option by
     bequest or inheritance may exercise the Option within five years after the
     death of the Optionee.



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          (c) Neither the transfer of the Optionee between any combination of
     the Company, its parent and any subsidiary of the Company, nor a leave of
     absence granted to the Optionee and approved by the Committee, shall be
     deemed a termination of employment. The terms "parent" and "subsidiary" as
     used herein shall have the meaning ascribed to "parent corporation" and
     "subsidiary corporation," respectively in Sections 424(e) and (f) (or
     successor provisions) of the Internal Revenue Code of 1986, as amended.

          6. ACCELERATION OF OPTION.

          (a) DEATH, DISABILITY OR RETIREMENT. If any of Sections (5)(a)(ii),
     5(a)(iii) or 5(b) of this Agreement is applicable, the Option, whether or
     not previously exercisable, shall become immediately exercisable in full if
     the Optionee shall have been employed continuously by the Company or a
     parent or subsidiary thereof between the date the Option was granted and
     the date of such Disability or Normal Retirement or, in the event of death,
     a date not more than three months prior to such death.

          (b) CHANGE OF CONTROL. In the event of a Change of Control (as defined
     in the Plan):

               (i) SUBSTITUTE OPTIONS. Subject to the provisions of clause (iii)
               below, after the effective date of such Change of Control, the
               Optionee shall be entitled, upon exercise of the Option, to
               receive, in lieu of shares of the Company's Common Stock (or
               consideration based upon the Fair Market Value of the Company's
               Common Stock), shares of such stock or other securities, cash or
               property (or consideration based upon shares of such stock or
               other securities, cash or property) as the holders of shares of
               the Company's Common Stock received in connection with the Change
               of Control.

               (ii) PARTIAL ACCELERATION. Notwithstanding any other provision of
               this Section 6, one hundred-percent (100%) of the Shares which
               are not then exercisable shall become exercisable upon the
               occurrence of a Change of Control if the Optionee is an employee
               of the Company immediately before the occurrence of the Change of
               Control and (1) the Optionee's employment with the Company is
               terminated by the Company (including any successor or parent
               resulting from the Change in Control) without Cause within six
               (6) months after the Change in Control, or (2) the Company (or
               successor) does not offer the Optionee a Comparable Position upon
               the Change in Control, or (3), if the Optionee is offered and
               accepts a Comparable Position, the Optionee is involuntarily
               removed from such position within six (6) months after the Change
               in Control. For the purpose of this Section 6(b), the term
               "Comparable Position" shall mean a position of employment with
               the Company or its successor following a Change of Control (or if
               the Company or its successor has a Parent following a Change of
               Control, its Parent) (X) with substantially the same or superior
               title, responsibilities, base salary, opportunity for incentive
               compensation, and eligibility for stock options or other equity
               incentives as the Optionee had prior to the Change of Control,
               and (Y) at a location within 50 miles of the Optionee's location
               prior to the Change of Control, without the Optionee's express
               prior written consent. For the purpose of this Section 6(b) the
               term "Cause" shall mean (A) substantial failure by or refusal of
               the Optionee to perform the Optionee's duties to the Company,
               gross neglect of such duties, or other material breach of the
               Optionee's written or oral employment agreement with the Company,
               as the case may be; (B) material misappropriation by the Optionee
               of the Company's property or trade secrets, commission of a
               felony by the Optionee or other public misconduct by the Optionee
               detrimental to the reputation of the Company or (C) material
               dishonesty or material violation of any fiduciary duty or duty of
               loyalty owed by the Optionee to the Company.



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               (iii) ACCELERATION OF VESTING AND NOTICE OF CANCELLATION. The
               Committee may cancel the Option as of the effective date of any
               such Change of Control provided that (x) all Shares that have not
               yet become exercisable shall become exercisable in full
               immediately prior to such Change of Control, (y) notice of such
               cancellation shall be given to the Optionee and (z) the Optionee
               shall have the right to exercise the Option, including exercising
               Shares that became exercisable pursuant to the acceleration
               provisions of clause (x) above.

          (c) EARLY EXERCISE FOR RESTRICTED SHARES. The Optionee may exercise
     the Option in accordance with this Section 6(c) for shares of the Company's
     Common Stock prior to the date or dates upon which such shares become
     exercisable under Section 3(a), and the exercise schedule in the Notice
     shall be deemed to have been accelerated for such purpose, provided,
     however, that in no event shall the Optionee be permitted pursuant to this
     Section 6(c) to exercise in any calendar year more than the $100,000
     Limitation Amount. For these purposes, the "$100,000 Limitation Amount"
     shall mean the number of shares of the Company's Common Stock equal to (i)
     $100,000 less the Prior Grant Amount divided by (ii) the exercise price per
     share specified in the Notice; and the "Prior Grant Amount" shall mean the
     number of shares of the Company's Common Stock becoming exercisable in such
     calendar year pursuant to incentive stock options granted to the Holder by
     the Company (or a company acquired by the Company) prior to the date this
     Option was granted multiplied by the exercise price of such options. The
     shares issued upon such early exercise shall be subject to the restrictions
     set forth in this subsection, and are referred to in this subsection as the
     "Restricted Shares."

               (i) REVERSE VESTING. Restricted Shares purchased under this
               Section 6(c) prior to the Option becoming exercisable shall
               "vest" according to the same schedule (i.e., on the same dates
               and in the same amounts) as such shares would have become
               purchasable upon exercise of the Option had the exercise schedule
               not been accelerated in accordance with this Section 6(c). In
               addition, Restricted Shares shall be subject to accelerated
               "vesting" as set forth in Section 6(a), Section 6(b)(ii) and
               Section 6(b)(iii) if applicable, to the same extent as the
               exercisability of such shares would have been accelerated had the
               exercise schedule not been previously accelerated in accordance
               with this Section 6(c). Restricted Shares that are not vested
               shall be subject to repurchase by the Company under Sections
               6(c)(ii) and 6(c)(iii) below. As Restricted Shares become vested
               they shall no longer be subject to repurchase by the Company.

               (ii) COMPANY REPURCHASE RIGHTS. In the event of termination of
               the Optionee's employment by the Company for any reason
               (including death, Disability, Normal Retirement and for Cause),
               the Company shall have the option to purchase all or any part of
               the Restricted Shares that were not vested prior to termination
               of the Optionee's employment (after taking into effect any
               accelerated vesting pursuant to Section 6(a), Section 6(b)(ii)
               and Section 6(b)(iii)) at a per share price equal to the purchase
               paid by the Optionee upon exercise of the Option (subject to
               equitable adjustment for any stock split, stock dividend or
               combination of the Restricted Shares).

               (iii) TERMS OF COMPANY PURCHASE. If the Company intends to
               repurchase the Restricted Shares subject to repurchase, then it
               shall, within sixty (60) days after termination of the Optionee's
               employment, mail written notice of its intent to repurchase the
               Restricted Shares and the number of Restricted Shares to be
               repurchased to the Optionee's last known address appearing in the
               personnel records of the Company. If the Company has not mailed
               notice within that period, the Restricted Shares will no longer
               be subject to repurchase by the Company. Upon receipt from the
               Optionee of the certificate for the Restricted Shares, duly
               endorsed in blank or accompanied by a duly endorsed blank stock
               power suitable for transferring the Shares to the Company, the
               Company shall send to the Optionee (or his or her heir legatee,
               representative or guardian) the purchase price for the Restricted
               Shares and a certificate for the shares which are not subject to
               repurchase or are not being repurchased by the Company. The
               purchase price for the Restricted Shares being repurchased may be
               payable by check, by cancellation of all or a portion of any
               outstanding



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               indebtedness of the Optionee to the Company, or both. If the
               Company has not received the certificate for the Restricted
               Shares by the time the Company is prepared to pay the purchased
               price for such shares, then the Company, at its option, may
               coincident with the payment of the purchase price and/or
               cancellation of debt, make appropriate entries in the records of
               the Company to effect the transfer of the Restricted Shares to
               the Company free and clear of any liens or encumbrances.

               (iv) OPTIONEE REPRESENTATIONS. By exercising the shares under
               this subsection 6(c), the Optionee represents that (i) he or she
               is acquiring the Restricted Shares for investment and not with a
               view to, or for resale in connection with, any distribution
               thereof; (ii) the Restricted Shares are "restricted securities"
               within the meaning of Rule 144 promulgated under the Securities
               Act of 1933, as amended (the "Securities Act"), and that there is
               no assurance that such Rule will apply to future resales of the
               Restricted Shares; (iii) he or she will make no sale or other
               distribution that would cause the Optionee to be deemed an
               "underwriter" within the meaning of Section 2(11) of the
               Securities Act; and (iv) he or she will make no sale, pledge,
               transfer or other disposition of the Restricted Shares received
               except in accordance with this Agreement unless a registration
               statement with respect to the Restricted Shares is then in effect
               under applicable federal and state securities laws or unless he
               or she obtains an opinion of counsel satisfactory to the Company
               that such disposition may be effected without violation of
               applicable federal or state securities laws.

               (v) CERTIFICATES; LEGENDS. The certificates representing the
               Restricted Shares will bear restrictive legends noting the
               restrictions identified in the preceding clause, the Company's
               repurchase rights and the restrictions on transfer set forth in
               Section 7 of this Agreement.

          7. LIMITATION ON TRANSFER. During the lifetime of the Optionee, only
the Optionee or his or her guardian or legal representative or transferee of a
transfer permitted by this Section may exercise the Option. The Optionee shall
not assign or transfer the Option or Restricted Shares issued upon early
exercise of the Option, except that the Optionee may transfer the Option by will
or the laws of descent and distribution. Any attempt to assign, transfer,
pledge, hypothecate or otherwise dispose of the Option or any Restricted Shares
contrary to the provisions hereof, and the levy of any attachment or similar
process upon the Option or any Restricted Shares, shall be null and void.

          8. SHAREHOLDER RIGHTS BEFORE EXERCISE. The Optionee shall have none of
the rights of a shareholder of the Company with respect to any Share subject to
the Option until the Share is actually issued to him or her upon exercise of the
Option.

          9. ADJUSTMENTS. The Committee may in its sole discretion make
appropriate adjustments in the number of Shares subject to the Option and in the
purchase price per Share to give effect to any adjustments made in the number of
outstanding Shares of the Company through a merger or consolidation (that is not
a Change in Control) or a recapitalization, stock dividend, stock split or other
relevant change, provided that fractional Shares shall be rounded to the nearest
whole share.

          10. DISQUALIFYING DISPOSITIONS. The Optionee agrees to notify the
Company in writing immediately after making a Disqualifying Disposition of any
shares of Common Stock received pursuant to the exercise of this Option. A
"Disqualifying Disposition" shall have the meaning specified in Section 421(b)
of the Internal Revenue Code of 1986, as amended, or any successor provision.
The Optionee also agrees to provide the Company with any information that the
Company shall request concerning any such Disqualifying Disposition. The
Optionee acknowledges that he or she will forfeit the favorable income tax
treatment otherwise available with respect to the exercise of this Option if he
or she makes a Disqualifying Disposition of shares received upon exercise of
this Option.

          11. TAX WITHHOLDING. The Optionee agrees that if the Company in its
discretion determines that it is obligated to withhold tax with respect to a
Disqualifying Disposition of shares of Common Stock received upon exercise of
this Option, then the Company may withhold from the Optionee's wages the
appropriate amount of federal, state or local withholding taxes



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attributable to such Disqualifying Disposition. If any portion of this Option is
treated as a Nonqualified Option (as defined in the Plan), the Optionee hereby
agrees that the Company may withhold from the Optionee's wages the appropriate
amount of federal, state and local withholding taxes attributable to the
Optionee's exercise of such Nonqualified Option. The Optionee further agrees
that, at the time he or she exercises the Option, if the Company or a parent or
subsidiary thereof is required to withhold such taxes, he or she will promptly
pay in cash upon demand to the Company, or the parent or subsidiary having such
obligation, such amounts as shall be necessary to satisfy such obligation;
provided, however, that in lieu of all or any part of such a cash payment, the
Board may, but shall not be required to, permit the Optionee to elect to cover
all or any part of the required withholdings, and to cover any additional
withholdings up to the amount needed to cover the Optionee's full FICA and
federal, state and local income taxes with respect to income arising from the
exercise of the Option, through a reduction of the number of Shares delivered to
the Optionee.

          12. LOCK UP AGREEMENT. Optionee agrees that, upon the request of the
Company or the managing underwriter(s) in connection with a registration of
shares of the Company's Common Stock pursuant to Section 12 of the Securities
Exchange Act of 1934 (the "Exchange Act") for a period of time (not to exceed
180 days) from the effective date of the Company's registration under Section 12
of the Exchange Act, Optionee (or any transferee permitted under this Agreement)
shall not sell, make any short sale of, loan, grant any option for the purchase
of, or otherwise dispose of any shares of the Company's Common Stock owned or
controlled by it; provided, however, that, at the time of the request, the
Optionee is an officer or a member of the board of directors of the Company or
the Optionee holds (assuming exercise of all options and warrants, and the
conversion of all convertible securities held by the Optionee, to the extent
then exercisable or convertible) an aggregate number of shares of the Company's
Common Stock (or equivalent) equal to at least one percent (1%) of the total
number of shares of the Company's Common Stock then issued and outstanding.

          13. INTERPRETATION OF THIS AGREEMENT. All decisions and
interpretations made by the Committee with regard to any question arising
hereunder or under the Plan shall be binding and conclusive upon the Company and
the Optionee. In the event that there is any inconsistency between the
provisions of this Agreement and the Plan, the provisions of the Plan shall
govern.

          14. DISCONTINUANCE OF EMPLOYMENT. This Agreement shall not give the
Optionee a right to continued employment with the Company or any parent or
subsidiary thereof, and the Company or any such parent or subsidiary thereof
employing the Optionee may terminate his or her employment and otherwise deal
with the Optionee without regard to the effect it may have upon him or her under
this Agreement.

          15. GENERAL. The Company shall at all times during the term of this
Option reserve and keep available such number of Shares as will be sufficient to
satisfy the requirements of this Agreement. This Agreement shall be binding in
all respects on the Optionee's heirs, representatives, successors and assigns.
This Agreement is entered into under the laws of the State of Delaware, without
regard to its principles of conflict of laws, and shall be construed and
interpreted thereunder.


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