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                             ZEPPELIN SOFTWARE, INC.
                        1998 INCENTIVE STOCK OPTION PLAN

1     OPTIONS GRANTED UNDER PLAN. Under this Incentive Stock Option Plan
(the "Plan") of Zeppelin Software, Inc. (the "Company") stock options which
qualify as incentive stock options ("Options") under Section 422 of the Internal
Revenue Code of 1986, as amended (the "Code"), may be granted to eligible
employees to purchase shares of the Company's capital stock. The Plan is
designed to enable the Company to attract, retain and motivate its employees by
providing for or increasing the proprietary interests of such employees in the
Company.

2     STOCK SUBJECT TO PLAN. The maximum number of shares of the Company's
common stock (the "Common Stock") subject to this Plan and for which Options
granted hereunder may therefore be exercised will be established by the
Company's Board of Directors (the "Board"). Shares of Common Stock subject to
the unexercised portions of any Options granted under this Plan which expire or
terminate or are canceled may again be subject to Options under the Plan.

3     ELIGIBLE EMPLOYEES. The employees eligible to be considered for the
grant of Options hereunder are any persons regularly employed by the Company in
any capacity on a full-time, salaried basis.

4     OPTION TERMS.

         4.1 EXERCISE PRICE. Except as otherwise provided herein, the exercise
price for each Option granted hereunder will be fixed by the Board and will be
not less than 100% of the Fair Market Value (as defined in Section 14 herein) of
the Common Stock on the date of the grant of the Option. Neither the Company,
the Board nor any member thereof makes or will make any representation or
warranty to any participant regarding the Federal or State income tax
consequences or effects of participation in the Plan.

         4.2 GRANTING OF OPTIONS. Subject to the provisions and limitations of
this Plan, and subject to applicable securities, tax and other laws and
regulations, Options may be granted at such time or times and pursuant to such
terms and conditions as may be determined by the Board.

         4.3 DURATION. Options may not be granted under this Plan after December
31, 2007. Each Option will provide that it may be exercised in not less than
such number of installments as set forth in the "Stock Option Agreement" for
such Option between the Company and the Optionee; provided, however, that no
Option will be exercised in full or in part after the expiration of ten (10)
years from the date such Option is granted.

         4.4 PAYMENT. Payment for Common Stock purchased upon any exercise of an
Option granted under this Plan will be made in full in cash (including payment
by check) concurrently with such exercise.

         4.5 CESSATION OF EMPLOYMENT. Except as otherwise specifically provided
in the Stock Option Agreement, in the event an Optionee retires or otherwise
ceases to be employed by the Company for any reason, including leaves of
absences (other than a termination by death, permanent or total disability
within the

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meaning of Section 22(e) of the Code, or for cause), such Optionee will have the
right to exercise any Options which became exercisable prior to retirement or
cessation of employment but only within a period of three (3) months from the
date of cessation of employment (but in any event not later than the termination
date of the Option), after which time any unexercised portion of all outstanding
Options will expire. In no event and under no circumstances may an Option be
exercised by an employee (or his personal representative) after termination of
the Optionee's employment for cause.

         4.6 DISABILITY. In the case of an Optionee who becomes permanently
disabled within the meaning of Section 22(e)(3) of the Code while in the employ
of the Company, any Option which was exercisable on the date when such Optionee
became disabled may be exercised within one (1) year after such Optionee ceases
employment (but in no event later than the termination date of the Option) after
which time any unexercised portion of all outstanding Options will expire.

         4.7 DEATH. In the event of the death of an Optionee while in the employ
of the Company, the estate of the deceased Optionee will have the right to
exercise any Options which became exercisable prior to the Optionee's death but
only within a period of one year from the date of the Optionee's death (but in
no event later that the termination date of the Option) after which time any
unexercised portion of all outstanding Options will expire. In the event an
Option is exercised by the estate of an Optionee, the Company will be under no
obligation to issue shares of Common Stock upon exercise unless and until the
Company is satisfied that the person exercising the Option is the duly appointed
legal representative of the Optionee's estate.

         4.8 NONTRANSFERABILITY. Each Option granted under this Plan is
nontransferable by the Optionee other than by will or the laws of descent and
distribution, and is exercisable only in accordance with the provisions of this
Plan.

5 STOCK OPTION AGREEMENT. Each Option granted under this Plan will be evidenced
by a Stock Option Agreement. All forms of Stock Option Agreement will contain
such provisions, restrictions, and conditions as are not inconsistent with this
Plan but need not be identical. The provisions of this Plan will be incorporated
by reference in each Stock Option Agreement. Options granted under this Plan
will contain such other terms and provisions as the Board may authorize,
including but not limited to:

         (i)   vesting schedules governing the exercisability of such Options;

         (ii)  provisions for acceleration of such vesting schedules in certain
               events;

         (iii) arrangements whereby the Company may fulfill any tax withholding
               obligations it may have in connection with the exercise of such
               Options;

         (iv)  provisions imposing restrictions upon the transferability of
               shares of Common Stock acquired on exercise of such Option,
               whether required by this Plan or applicable securities laws or
               imposed for other reasons; and

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         (v)   provisions regarding the termination or survival of any such
               Option upon the Optionee's death, retirement or other
               terminations of employment and the extent, if any, to which any
               such Option may be exercised after such event.

6     ADJUSTMENTS. In the event the Common Stock is changed into or
exchanged for a different number or kind of shares of stock or other securities
of the Company or of another corporation (whether by reason of merger,
consolidation, reorganization or otherwise), or if the number of outstanding
shares of Common Stock are increased through a stock split or the payment of a
stock dividend, then there will be substituted for or added to each share of
Common Stock which is subject to an Option, the number and kind of shares of
securities into which each outstanding share of Common Stock is changed.
Outstanding Options will also be amended as to price and other terms if
necessary to reflect the foregoing events. No right to purchase fractional
shares will result from any adjustment in Options pursuant to this Section 6. In
case of any such adjustment, the shares subject to the Option will be rounded
down to the nearest whole share. Notice of any adjustment will be given by the
Company to each Optionee which will have been so adjusted and such adjustment
(whether or not notice is given) will be effective and binding for all purposes
of the Plan. Any other provision hereof to the contrary notwithstanding, in the
event the Company is a party to a merger or other reorganization, outstanding
Options will be subject to the agreement of merger or reorganization. Such
agreement may provide, without limitation, for the assumption of outstanding
Options by the surviving company or its parent, for the continuation by the
Company (if the Company is a surviving entity), for accelerated vesting and
accelerated expiration, or for settlement in cash

7     ADMINISTRATION. The Plan will be administered by the Company's board
of directors (the "Board") or a committee appointed by the Board (the
"Committee"). For purposes of this Plan and any Stock Option Agreement, any
action taken with respect to this Plan or any Stock Option Agreement by the
Committee will be binding in the same manner as if such action were taken by the
Board. The interpretation and construction by the Board of any term or provision
of the Plan or of any Option granted under it, including without limitation any
determination of adjustments required pursuant to Section 6 hereof, will be
conclusive, and such interpretation and construction will be binding upon all
those who hold or are eligible to receive Options under the Plan. The Board or
Committee may from time to time adopt rules and regulations for carrying out
this Plan and, subject to the provisions of this Plan, may prescribe the form of
the instruments evidencing any Option granted under this Plan. Subject to the
provisions of this Plan, the Board will have full and final authority in its
discretion to select the employees to be granted Options, to authorize granting
such Options and to determine the number of shares to be subject thereto, the
exercise prices, the terms of exercise, expiration dates and other pertinent
provisions thereof.

8     AMENDMENT AND TERMINATION. The Board may alter, amend, suspend or
terminate this Plan, provided that no such action will deprive any of the
Optionee's rights under an Option without the

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Optionee's consent. Except as herein provided, no such action of the Board,
unless taken with the approval of the stockholders of the Company, may:

         (i)   increase the maximum number of shares for which Options granted
               under this Plan may be exercised;

         (ii)  reduce the minimum permissible exercise price;

         (iii) alter the class of employees eligible to receive Options under
               the Plan; or

         (iv)  amend the Plan in any other manner which the Board, in its
               discretion, determines should become effective only if approved
               by the stockholders even though such stockholder approval is not
               expressly required by this Plan.

9        FINANCIAL ASSISTANCE. The Company is vested with authority under this
Plan to assist any employee to whom an Option is granted hereunder (including
any director or officer of the Company or any of its subsidiaries who is also an
employee) in the payment of the purchase price payable on exercise of that
Option, by lending the amount of such purchase price to such employee on such
terms and at such rates of interest and upon such security (or unsecured) as
will have been authorized by or under authority of the Board.

10    LIMITATIONS OF RIGHTS OF OPTIONEES.

         10.1 CERTIFICATES. A person to whom an Option is granted under this
Plan will not have any interest in the shares of Common Stock underlying the
Option, and will not have any of the rights or privileges of a shareholder with
respect to such shares, until the Option is exercised and the shares of Common
Stock are purchased.

         10.2 NO VIOLATIONS. No shares of stock issuable under the Plan will be
issued and no certificate therefor delivered unless and until, in the opinion of
legal counsel for the Company, such securities may be issued and delivered
without causing the Company to be in violation of or to incur any liability
under any federal, state or other securities law, or any other requirement of
law or of any regulatory body having jurisdiction over the Company.

         10.3 NO RIGHT TO EMPLOYMENT. The receipt of an Option does not give the
Optionee any right to continued employment by the Company for any period, nor
will the granting of the Option or the issuance of shares on exercise thereof
give the Company any right to the continued services of the Optionee for any
period.

         10.4 EXPRESS GRANT. Nothing contained in this Plan will constitute the
granting of an Option hereunder, which will occur only pursuant to express
authorization by the Board or the Committee.

         11 COMPANY'S RIGHT OF FIRST PURCHASE. Until such time as the Company=s
Common Stock is Publicly Traded, any shares of Common Stock issued upon the
exercise of any Option will be subject to the Company's right of first purchase.
By virtue of that right, (a) such shares of Common Stock may not be transferred
during the Optionee's lifetime to any person other than members of the
Optionee's Immediate Family, a partnership whose members are the Optionee and/or
members of the Optionee's Immediate Family, or a trust for the benefit of the
Optionee and/or members of the


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Optionee's Immediate Family, unless such transfer occurs within the 30 days
immediately following either (i) the expiration of 30 days following written
notice by the Optionee to the Company identifying the prospective transferee and
offering the Company the first opportunity to purchase such stock at its Fair
Market Value in cash, or (ii) the Company's election to not purchase such shares
of Common Stock after receipt of such notice; and (b) upon the Optionee's death,
the Company will have the right to purchase all or some of such stock at its
Fair Market Value within nine months after the date of death. This right of
first purchase will continue to apply to any such stock after the transfer
during the Optionee's lifetime of that stock to a member of the Optionee's
Immediate Family or to a family partnership or trust as aforesaid, and after any
transfer of that stock with respect to which the Company expressly waived its
right of first purchase without also waiving it as to any subsequent transfers
thereof, but it will not apply after a transfer of that stock with respect to
which the Company was offered but did not exercise or waive its right of first
purchase or more than nine months after the Optionee's death. The Company may
assign all or any portion of its right of first purchase to any one or more of
its stockholders, or to a pension or retirement plan or trust for employees of
the Company, who may then exercise the right so assigned.

12    LEGENDS ON SHARE CERTIFICATES.

         12.1 For so long as the Common Stock is not Publicly Traded, in
addition to any other legends which may be prescribed by law, the following
legend (or substantially the following legend) will appear on each certificate
representing the Common Shares issued upon the exercise of each Option:

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE BEEN
                  ISSUED AND ARE BEING HELD PURSUANT TO THE 1998 INCENTIVE STOCK
                  OPTION PLAN OF ZEPPELIN SOFTWARE, INC., AND MAY ONLY BE
                  TRANSFERRED, SOLD OR OTHERWISE DISPOSED OF PURSUANT TO THE
                  TERMS THEREOF."

         12.2 For so long as the Common Stock is not Publicy Traded, the
certificates representing the Common shares may, at the absolute discretion of
the Company, be subject to a stop transfer order, and bear the following or
substantially similar legend and such other legends as may be required by the
Company:

                  "THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN
                  REGISTERED UNDER THE SECURITIES ACT OF 1933, AS AMENDED (THE
                  "ACT"), OR ANY STATE SECURITIES LAWS AND NEITHER SUCH
                  SECURITIES NOR ANY INTEREST THEREIN MAY BE OFFERED, SOLD,
                  PLEDGED, ASSIGNED OR OTHERWISE TRANSFERRED UNLESS (1) A
                  REGISTRATION STATEMENT WITH RESPECT THERETO IS EFFECTIVE UNDER
                  THE ACT AND ANY APPLICABLE STATE SECURITIES LAWS OR (2) THE
                  COMPANY RECEIVES AN OPINION OF COUNSEL TO THE HOLDER OF SUCH
                  SECURITIES, WHICH COUNSEL AND OPINION ARE REASONABLY
                  SATISFACTORY TO THE COMPANY, THAT SUCH SECURITIES MAY BE
                  OFFERED, SOLD, PLEDGED, ASSIGNED OR TRANSFERRED IN THE MANNER
                  CONTEMPLATED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT UNDER
                  THE ACT OR APPLICABLE STATE SECURITIES LAWS."

13    CERTAIN DEFINITIONS. In addition to the terms defined elsewhere in this
Plan, the following terms will have the following definitions:


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13.1  FAIR MARKET VALUE DEFINED. The "Fair Market Value" of corporate stock
will mean the price at which one could reasonably expect such stock to be sold
in an arm's length transaction, for cash, other than on an installment basis, to
a person not employed by, controlled by, in control of or under common control
with the issuer of such stock. Such Fair Market Value will be that which has
currently or most recently been determined for this purpose by the Board, or at
the sole discretion of the Board by an independent appraiser or appraisers
selected by the Board, in either case giving due consideration to recent
transactions involving shares of such stock, if any, the issuer's net worth,
prospective earning power and dividend-paying capacity, the goodwill of the
issuer's business, the issuer's industry position and its management, that
industry's economic outlook, the values of securities of issuers whose stock is
publicly traded and which are engaged in similar businesses, the effect of
transfer restrictions to which such stock may be subject under law and under the
applicable terms of any contract governing such stock, the absence of a public
market for such stock and such other matters as the Board or its appraiser or
appraisers deem pertinent. The determination by the Board or its appraiser or
appraisers of the Fair Market Value will, if not unreasonable, be conclusive and
binding notwithstanding the possibility that other persons might make a
different, and also reasonable, determination. If the Fair Market Value to be
used was thus fixed more than sixteen months prior to the day as of which Fair
Market Value is being determined, it will in any event be no less than the book
value of the stock being valued at the end of the most recent period for which
financial statements of the issuer are available.

13.2  IMMEDIATE FAMILY. An individual's "Immediate Family" includes only his
or her spouse, parents or other ancestors, and children and other direct
descendants of that individual or of his or her spouse (including such ancestors
and descendants by adoption).

13.3  PUBLICLY TRADED. Corporate stock is "Publicly Traded" if stock of that
class is listed or admitted to unlisted trading privileges on a national
securities exchange or designated as a national market system security on an
interdealer quotation system by the National Association of Securities Dealers,
Inc. ("NASD") or if sales or bid and offer quotations are reported for that
class of stock in the automated quotation system ("NASDAQ") operated by the
NASD.

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