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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.


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               (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:

                    (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).


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               (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.

               (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, fifty-percent (50%) 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 (A) 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.

                    (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


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                    (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 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


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                    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
     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


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     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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