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                                                                     EXHIBIT 4.3

                          REGISTRATION RIGHTS AGREEMENT


               This Registration Rights Agreement (this "Agreement") is made and
entered into as of August 28, 1997, by and among Cayenne Software, Inc., a
Massachusetts corporation (the "Company"), and the several purchasers identified
in Schedule A attached hereto (the "Purchasers").

               This Agreement is made pursuant to the Convertible Preferred
Stock Purchase Agreement, dated as of the date hereof, by and among the Company
and the Purchasers (the "Purchase Agreement"). The execution of this Agreement
is a condition to the closing of the transactions contemplated by the Purchase
Agreement.

               The Company and the Purchaser hereby agree as follows:

      6.       Definitions

               Capitalized terms used and not otherwise defined herein shall
have the meanings given such terms in the Purchase Agreement. As used in this
Agreement, the following terms shall have the following meanings:

               "Advice" shall have meaning set forth in Section 3(o).

               "Affiliate" means, with respect to any Person, any other Person
that directly or indirectly controls or is controlled by or under common control
with such Person. For the purposes of this definition, "control," when used with
respect to any Person, means the possession, direct or indirect, of the power to
direct or cause the direction of the management and policies of such Person,
whether through the ownership of voting securities, by contract or otherwise;
and the terms of "affiliated," "controlling" and "controlled" have meanings
correlative to the foregoing.

               "Business Day" means any day except Saturday, Sunday and any day
which shall be a legal holiday or a day on which banking institutions in the
state of New York generally are authorized or required by law or other
government actions to close.

               "Certificate of Vote" shall have the meaning set forth in 
Section 4.

               "Commission" means the Securities and Exchange Commission.

               "Common Stock" means the Company's Common Stock, par value $0.01
per share.

               "Effectiveness Date" means with respect to the Registration
Statement to be filed with respect to the Series D Shares, the 120th day
following the Series D Closing Date.

               "Effectiveness Period" shall have the meaning set forth in
Section 2(a).


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               "Event" shall have the meaning set forth in Section 4.

               "Event Date" shall have the meaning set forth in Section 4.

               "Exchange Act" means the Securities Exchange Act of 1934, as
amended.

               "Filing Date" means with respect to the shares of Common Stock
issuable upon conversion of the Series D Shares and the Series D Warrants, the
30th day following the Series D Closing Date.

               "Holder" or "Holders" means the holder or holders, as the case
may be, from time to time of Registrable Securities.

               "Indemnified Party" shall have the meaning set forth in Section
6(c).

               "Indemnifying Party" shall have the meaning set forth in Section
6(c).

               "Losses" shall have the meaning set forth in Section 6(a).

               "Managing Underwriter" means any managing underwriter retained by
a Holder in connection with the offer and sale of Registrable Securities.

               "Person" means an individual or a corporation, partnership,
trust, incorporated or unincorporated association, joint venture, limited
liability company, joint stock company, government (or an agency or political
subdivision thereof) or other entity of any kind.

               "Preferred Stock" means the shares of Series D Convertible
Preferred Stock, par value $1.00 per share, of the Company issued to the
Purchaser pursuant to the Purchase Agreement.

               "Proceeding" means an action, claim, suit, investigation or
proceeding (including, without limitation, an investigation or partial
proceeding, such as a deposition), whether commenced or threatened.

               "Prospectus" means the prospectus included in the Registration
Statement (including, without limitation, a prospectus that includes any
information previously omitted from a prospectus filed as part of an effective
registration statement in reliance upon Rule 430A promulgated under the
Securities Act), as amended or supplemented by any prospectus supplement, with
respect to the terms of the offering of any portion of the Registrable
Securities covered by the Registration Statement, and all other amendments and
supplements to the Prospectus, including post-effective amendments, and all
material incorporated by reference or deemed to be incorporated by reference in
such Prospectus.

               "Registrable Securities" means with respect to the Registration
Statement to be filed after the Series D Closing, the shares of Common Stock
issuable upon conversion of the Series D Shares, shares of Common Stock issuable
upon exercise of the Series D Warrants, and shares of Common Stock issuable as
payment of dividends on the Series D Shares; provided, however that in order to
account for the fact that the number of shares of Common Stock that are issuable
upon conversion of shares of Preferred Stock is determined in part upon the
market price of the Common Stock at the time of conversion, Registrable
Securities shall


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include a number of shares of Common Stock equal to no less than the sum of (1)
the greater of (x) 125% of the number of shares issuable upon conversion of all
the Series D Shares outstanding from time to time and (y) two times the number
of shares of Common Stock issuable upon conversion in full of the Series D
Share, assuming such conversion occurred on the particular Closing Date for such
shares of Preferred Stock, (2) the number of shares of Common Stock issuable
upon exercise in full of the Series D Warrants, assuming such exercise occurred
on the particular issuance date for such Warrants, and (3) the number of Shares
of Common Stock issuable on payment of dividends on the Series D Shares for the
one year period after the applicable Closing Date, or such other number of
shares of Common Stock as agreed to by the parties to the Purchase Agreement.
Notwithstanding anything herein contained to the contrary, if the actual number
of shares of Common Stock into which the Preferred Stock is convertible exceeds
twice the number of shares of Common Stock into which particular shares of
Preferred Stock are convertible based upon a computation as at a particular
Closing Date, the term "Registrable Securities" shall be deemed to include such
additional shares of Common Stock. If an additional Registration Statement is
required to be filed because the actual number of shares of Common Stock into
which the Preferred Stock are convertible, plus shares issuable upon payment of
dividends as described above and shares issuable upon exercise of the Warrants
exceeds the number of shares of Common Stock initially registered in respect of
any particular series of Preferred Stock based upon the computation on a
particular Closing Date, the Company shall have 10 Business Days after it makes
such a determination or receives notice from the Holders of Registrable
Securities as to such a determination to file such additional Registration
Statement in accordance with the terms hereof.

               "Registration Statement" means the registration statement,
contemplated by Section 2(a) (and any additional Registration Statements
contemplated in the definition of Registrable Securities), including (in each
case) the Prospectus, amendments and supplements to such registration statement
or Prospectus, including pre- and post-effective amendments, all exhibits
thereto, and all material incorporated by reference or deemed to be incorporated
by reference in such registration statement.

               "Rule 144" means Rule 144 promulgated by the Commission pursuant
to the Securities Act, as such Rule may be amended from time to time, or any
similar rule or regulation hereafter adopted by the Commission having
substantially the same effect as such Rule.

               "Rule 158" means Rule 158 promulgated by the Commission pursuant
to the Securities Act, as such Rule may be amended from time to time, or any
similar rule or regulation hereafter adopted by the Commission having
substantially the same effect as such Rule.

               "Rule 415" means Rule 415 promulgated by the Commission pursuant
to the Securities Act, as such Rule may be amended from time to time, or any
similar rule or regulation hereafter adopted by the Commission having
substantially the same effect as such Rule.

               "Securities Act" means the Securities Act of 1933, as amended.

               "Series D Closing Date" means the date of the issuance and sale
of the Series D Shares pursuant to the Purchase Agreement.


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               "Series D Shares" means the shares of Preferred Stock issued and
sold on the Series D Closing Date pursuant to the Purchase Agreement.

               "Special Counsel" means any special counsel to the Holders, for
which the Holders will be reimbursed by the Company pursuant to Section 4.

               "Underwriter" means any underwriter retained by a Holder in
connection with the offer and sale of Registrable Securities.

               "Underwritten Registration or Underwritten Offering" means a
registration in connection with which securities of the Company are sold to an
underwriter for reoffering to the public pursuant to an effective registration
statement.

               "Warrants" means the Common Stock purchase warrants issued to or
as directed by the Purchaser on each Closing Date.

      7.       Shelf Registration

               (a)   On or prior to each applicable Filing Date the Company 
shall prepare and file with the Commission a "Shelf" Registration Statement
covering all Registrable Securi ties for an offering to be made on a continuous
basis pursuant to Rule 415. The Registration Statement shall be on Form S-3 (or
another appropriate form approved by the Holders of a majority of the
Registrable Securities that permit registration of Registrable Securities for
resale by the Holders in the manner or manners designated by them (including,
without limitation, public or private sales and one or more Underwritten
Offerings)). The Company shall (i) not without the consent of the Holders
participating as selling stockholders in the registration, which consent will
not be withheld unreasonably, permit any securities other than the Registrable
Securities and those securities specifically listed on Schedule 8 attached
hereto, to be included in the Registration Statement and (ii) use its best
efforts to cause the Registration Statement to be declared effective under the
Securities Act as promptly as possible after the filing thereof, but in any
event prior to the Effectiveness Date, and to keep such Registration Statement
continuously effective under the Securities Act until the date which is two
years after the date that such Registration Statement is declared effective by
the Commission or such earlier date when all Registrable Securities covered by
such Registration Statement have been sold or may be sold pursuant to Rule 144
without volume restrictions as determined by the counsel to the Company pursuant
to a written opinion letter, addressed to the Holders, to such effect (the
"Effectiveness Period"); provided, however, that the Company shall not be deemed
to have used its best efforts to keep the Registration Statement effective
during the Effectiveness Period if it voluntarily takes any action that would
result in the Holders not being able to sell the Registrable Securities covered
by such Registration Statement during the Effectiveness Period, unless such
action is required under applicable law or the Company has filed a
post-effective amendment to the Registration Statement and the Commission has
not declared it effective.

               (b)   If the Holders of a majority of the Registrable Securities 
so elect, an offering of Registrable Securities pursuant to the Registration
Statement may be effected in the form of an Underwritten Offering. In such
event, and if the Managing Underwriters advise the Company and such Holders in
writing that in their opinion the amount of Registrable Securities proposed to
be sold in such Underwritten Offering exceeds the amount of


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Registrable Securities which can be sold in such Underwritten Offering, there
shall be included in such Underwritten Offering the amount of such Registrable
Securities which in the opinion of such Managing Underwriters can be sold, and
such amount shall be allocated pro rata among the Holders proposing to sell
Registrable Securities in such Underwritten Offering.

               (c)   If any of the Registrable Securities are to be sold in an
Underwritten Offering, the investment banker or investment bankers and manager
or managers that will administer the offering will be selected by the Holders of
a majority of the Registrable Securities included in such offering. No Holder
may participate in any Underwritten Offering hereunder unless such Person (i)
agrees to sell its Registrable Securities on the basis provided in any
underwriting agreements approved by the Persons entitled hereunder to approve
such arrangements and (ii) completes and executes all questionnaires, powers of
attorney, indemnities, underwriting agreements and other documents required
under the terms of such arrangements.

      8.       Registration Procedures

               In connection with the Company's registration obligations
hereunder, the Company shall:

               (a)   Prepare and file with the Commission on or prior to the
Filing Date a Registration Statement on Form S-3 in accordance with the method
or methods of distribution thereof as specified by the Holders, and cause the
Registration Statement to become effective and remain effective as provided
herein; provided, however, that not less than five (5) Business Days prior to
the filing of the Registration Statement or any related Prospectus or any
amendment or supplement thereto (including any document that would be
incorporated or deemed to be incorporated therein by reference), the Company
shall (i) furnish to the Holders, their Special Counsel and any Managing
Underwriters, copies of all such documents proposed to be filed, which documents
(other than those incorporated or deemed to be incorporated by reference) will
be subject to the review of such Holders, their Special Counsel and such
Managing Underwriters, and (ii) cause its officers and directors, counsel and
independent certified public accountants to respond to such inquiries as shall
be necessary, in the reasonable opinion of respective counsel to such Holders
and such Underwriters, to conduct a reasonable investigation within the meaning
of the Securities Act. The Company shall not file the Registration Statement or
any such Prospectus or any amendments or supplements thereto to which the
Holders of a majority of the Registrable Securities, their Special Counsel, or
any Managing Underwriters, shall object.

               (b)   (i) Prepare and file with the Commission such amendments,
including post-effective amendments, to the Registration Statement as may be
necessary to keep the Registration Statement continuously effective for the
Effectiveness Period and prepare and file with the Commission such additional
Registration Statements in order to register for resale under the Securities Act
all of the Registrable Securities; (ii) cause the related Prospectus to be
amended or supplemented by any required Prospectus supplement, and as so
supplemented or amended to be filed pursuant to Rule 424 (or any similar
provisions then in force) promulgated under the Securities Act; (iii) respond as
promptly as practicable to any comments received from the Commission with
respect to the Registration Statement or any amendment thereto and promptly
provide the Holders true and complete copies of all correspondence from and to
the Commission relating to the Registration Statement; and (iv) comply with the
provisions of the Securities Act and the Exchange Act with respect to the
disposition of all Registrable Securities


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covered by the Registration Statement during the applicable period in accordance
with the intended methods of disposition by the Holders thereof set forth in the
Registration Statement as so amended or in such Prospectus as so supplemented.

               (c)   Notify the Holders of Registrable Securities to be sold,
their Special Counsel and any Managing Underwriters immediately (and, in the
case of (i)(A) below, not less than five (5) days prior to such filing) and (if
requested by any such Person) confirm such notice in writing no later than 3
Business Days following the day (i)(A) when a Prospectus or any Prospectus
supplement or post-effective amendment to the Registration Statement is proposed
to be filed; (B) when the Commission notifies the Company whether there will be
a "review" of such Registration Statement and whenever the Commission comments
on such Registration Statement; and (C) with respect to the Registration
Statement or any post-effective amendment, when the same has become effective;
(ii) of any request by the Commission or any other Federal or state governmental
authority for amendments or supplements to the Registration Statement or
Prospectus or for additional information; (iii) of the issuance by the
Commission of any stop order suspending the effectiveness of the Registration
Statement covering any or all of the Registrable Securities or the initiation of
any Proceedings for that purpose; (iv) if at any time any of the representations
and warranties of the Company contained in any agreement (including any
underwriting agreement) contemplated hereby ceases to be true and correct in all
material respects; (v) of the receipt by the Company of any notification with
respect to the suspension of the qualification or exemption from qualification
of any of the Registrable Securities for sale in any jurisdiction, or the
initiation or threatening of any Proceeding for such purpose; and (vi) of the
occurrence of any event that makes any statement made in the Registration
Statement or Prospectus or any document incorporated or deemed to be
incorporated therein by reference untrue in any material respect or that
requires any revisions to the Registration Statement, Prospectus or other
documents so that, in the case of the Registration Statement or the Prospectus,
as the case may be, it will not contain any untrue statement of a material fact
or omit to state any material fact required to be stated therein or necessary to
make the statements therein, in light of the circumstances under which they were
made, not misleading.

               (d)   Use its best efforts to avoid the issuance of, or, if 
issued, obtain the withdrawal of (i) any order suspending the effectiveness of
the Registration Statement or (ii) any suspension of the qualification (or
exemption from qualification) of any of the Registrable Securities for sale in
any jurisdiction, at the earliest practicable moment.

               (e)   If requested by any Managing Underwriter or the Holders of 
a majority of the Registrable Securities to be sold in connection with an
Underwritten Offering, (i) promptly incorporate in a Prospectus supplement or
post-effective amendment to the Registration Statement such information as such
Managing Underwriters and such Holders reasonably agree should be included
therein and (ii) make all required filings of such Prospectus supplement or such
post-effective amendment as soon as practicable after the Company has received
notification of the matters to be incorporated in such Prospectus supplement or
post-effective amendment; provided, however, that the Company shall not be
required to take any action pursuant to this Section 3(e) that would, in the
opinion of counsel for the Company, violate applicable law.

               (f)   Furnish to each Holder, their Special Counsel and any
Managing Underwriters, without charge, at least one conformed copy of each
Registration Statement and each amendment thereto, including financial
statements and schedules, all documents


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incorporated or deemed to be incorporated therein by reference, and all exhibits
to the extent requested by such Person (including those previously furnished or
incorporated by reference) promptly after the filing of such documents with the
Commission.

               (g)   Promptly deliver to each Holder, their Special Counsel, and
any Underwriters, without charge, as many copies of the Prospectus or
Prospectuses (including each form of prospectus) and each amendment or
supplement thereto as such Persons may reasonably request; and the Company
hereby consents to the use of such Prospectus and each amendment or supplement
thereto by each of the selling Holders and any Underwriters in con nection with
the offering and sale of the Registrable Securities covered by such Prospectus
and any amendment or supplement thereto.

               (h)   Prior to any public offering of Registrable Securities, use
its best efforts to register or qualify or cooperate with the selling Holders,
any Underwriters and their respective counsel in connection with the
registration or qualification (or exemption from such registration or
qualification) of such Registrable Securities for offer and sale under the
securities or Blue Sky laws of such jurisdictions within the United States as
any Holder or Underwriter requests in writing, to keep each such registration or
qualification (or exemption therefrom) effective during the Effectiveness Period
and to do any and all other acts or things necessary or advisable to enable the
disposition in such jurisdictions of the Registrable Securities covered by a
Registration Statement; provided, however, that the Company shall not be
required to qualify to do business or to file a general consent to service of
process in any jurisdiction.

               (i)   Cooperate with the Holders and any Managing Underwriters to
facilitate the timely preparation and delivery of certificates representing
Registrable Securities to be sold, which certificates shall be free of all
restrictive legends, and to enable such Registrable Securities to be in such
denominations and registered in such names as any such Managing Underwriters or
Holders may request at least two Business Days prior to any sale of Registrable
Securities.

               (j)   Upon the occurrence of any event contemplated by Section
3(c)(vi), as promptly as practicable, prepare a supplement or amendment,
including a post-effective amendment, to the Registration Statement or a
supplement to the related Prospectus or any document incorporated or deemed to
be incorporated therein by reference, and file any other required document so
that, as thereafter delivered, neither the Registration Statement nor such
Prospectus will contain an untrue statement of a material fact or omit to state
a material fact required to be stated therein or necessary to make the
statements therein, in light of the circumstances under which they were made,
not misleading.

               (k)   Use its best efforts to cause all Registrable Securities
relating to such Registration Statement to be listed on the Nasdaq National
Market and any other securities exchange, market or over-the-counter bulletin
board, if any, on which similar securities issued by the Company are then
listed.

               (l)   Enter into such agreements (including an underwriting
agreement in form, scope and substance as is customary in Underwritten
Offerings) and take all such other actions in connection therewith (including
those reasonably requested by any Managing Underwriters and the Holders of a
majority of the Registrable Securities being sold) in order to expedite or
facilitate the disposition of such Registrable Securities, and whether or not an


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underwriting agreement is entered into, (i) make such representations and
warranties to such Holders and such Underwriters as are customarily made by
issuers to underwriters in underwritten public offerings, and confirm the same
if and when requested; (ii) obtain and deliver copies thereof to each Holder and
the Managing Underwriters, if any, of opinions of counsel to the Company and
updates thereof addressed to each selling Holder and each such Underwriter, in
form, scope and substance reasonably satisfactory to any such Managing
Underwriters and Special Counsel to the selling Holders covering the matters
customarily covered in opinions requested in Underwritten Offerings and such
other matters as may be reasonably requested by such Special Counsel and
Underwriters; (iii) immediately prior to the effectiveness of the Registration
Statement, and, in the case of an Underwritten Offering, at the time of delivery
of any Registrable Securities sold pursuant thereto, obtain and deliver copies
to the Holders and the Managing Underwriters, if any, of "cold comfort" letters
and updates thereof from the independent certified public accountants of the
Company (and, if necessary, any other independent certified public accountants
of any subsidiary of the Company or of any business acquired by the Company for
which financial statements and financial data is, or is required to be, included
in the Registration Statement), addressed to each selling Holder and each of the
Underwriters, if any, in form and substance as are custom ary in connection with
Underwritten Offerings; (iv) if an underwriting agreement is entered into, the
same shall contain indemnification provisions and procedures no less favorable
to the selling Holders and the Underwriters, if any, than those set forth in
Section 7 (or such other provisions and procedures acceptable to the Managing
Underwriters, if any, and holders of a majority of Registrable Securities
participating in such Underwritten Offering); and (v) deliver such documents and
certificates as may be reasonably requested by the Holders of a majority of the
Registrable Securities being sold, their Special Counsel and any Managing
Underwriters to evidence the continued validity of the representations and
warranties made pursuant to clause 3(l)(i) above and to evidence compliance with
any customary conditions contained in the underwriting agreement or other
agreement entered into by the Company.

               (m)   Make available for inspection by the selling Holders, any
representative of such Holders, any Underwriter participating in any disposition
of Registrable Securities, and any attorney or accountant retained by such
selling Holders or Underwriters, at the offices where normally kept, during
reasonable business hours, all financial and other records, pertinent corporate
documents and properties of the Company and its subsidiaries, and cause the
officers, directors, agents and employees of the Company and its subsidiaries to
supply all information in each case requested by any such Holder,
representative, Underwriter, attorney or accountant in connection with the
Registration Statement; provided, however, that any information that is
determined in good faith by the Company in writing to be of a confidential
nature at the time of delivery of such information shall be kept confidential by
such Persons, unless (i) disclosure of such information is required by court or
administrative order or is necessary to respond to inquiries of regulatory
authorities; (ii) disclosure of such information, in the opinion of counsel to
such Person, is required by law; (iii) such information becomes generally
available to the public other than as a result of a disclosure or failure to
safeguard by such Person; or (iv) such information becomes available to such
Person from a source other than the Company and such source is not known by such
Person to be bound by a confidentiality agreement with the Company.

               (n)   Comply with all applicable rules and regulations of the
Commission and make generally available to its security holders earning
statements satisfying the provisions of Section 11(a) of the Securities Act and
Rule 158 not later than 45 days after the end of any 12-month period (or 90 days
after the end of any 12-month period if such period is a fiscal


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year) (i) commencing at the end of any fiscal quarter in which Registrable
Securities are sold to Underwriters in a firm commitment or best efforts
Underwritten Offering and (ii) if not sold to Underwriters in such an offering,
commencing on the first day of the first fiscal quarter of the Company after the
effective date of the Registration Statement, which statement shall cover said
12-month period, or end shorter periods as is consistent with the requirements
of Rule 158.

               (o)   Provide a CUSIP number for all Registrable Securities, not
later than the effective date of the Registration Statement.

               The Company may require each selling Holder to furnish to the
Company such information regarding the distribution of such Registrable
Securities as is required by law to be disclosed in the Registration Statement
and the Company may exclude from such registration the Registrable Securities of
any such Holder who unreasonably fails to furnish such information within a
reasonable time after receiving such request.

               If the Registration Statement refers to any Holder by name or
otherwise as the holder of any securities of the Company, then such Holder shall
have the right to require (i) the inclusion therein of language, in form and
substance reasonably satisfactory to such Holder, to the effect that the
ownership by such Holder of such securities is not to be construed as a
recommendation by such Holder of the investment quality of the Company's
securities covered thereby and that such ownership does not imply that such
Holder will assist in meeting any future financial requirements of the Company,
or (ii) if such reference to such Holder by name or otherwise is not required by
the Securities Act or any similar Federal statute then in force, the deletion of
the reference to such Holder in any amendment or supplement to the Registration
Statement filed or prepared subsequent to the time that such reference ceases to
be required.

               The Purchaser covenants and agrees that (i) it will not offer or
sell any Registrable Securities under the Registration Statement until it has
received copies of the Prospectus as then amended or supplemented as
contemplated in Section 3(g) and notice from the Company that such Registration
Statement and any post-effective amendments thereto have become effective as
contemplated by Section 3(c) and (ii) the Purchaser and its officers, directors
or Affiliates, if any, will comply with the prospectus delivery requirements of
the Securities Act as applicable to them in connection with sales of Registrable
Securities pursuant to the Registration Statement.

               Each Holder agrees by its acquisition of such Registrable
Securities that, upon receipt of a notice from the Company of the occurrence of
any event of the kind described in Section 3(c)(ii), 3(c)(iii), 3(c)(iv),
3(c)(v) or 3(c)(vi), such Holder will forthwith discontinue disposition of such
Registrable Securities until such Holder's receipt of the copies of the
supplemented Prospectus and/or amended Registration Statement contemplated by
Section 3(j), or until it is advised in writing (the "Advice") by the Company
that the use of the applicable Prospectus may be resumed, and, in either case,
has received copies of any additional or supplemental filings that are
incorporated or deemed to be incorporated by reference in such Prospectus or
Registration Statement.

               9. Liquidated Damages. The Company acknowledges and agrees that
the Holders will suffer damages, and that it would not be feasible to ascertain
the extent of such damages with precision, if (a) a Registration Statement shall
not have been filed with the


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Commission on or prior to the applicable Filing Date, or (b) the Company fails
to file with the Commission a request for acceleration in accordance with Rule
12d1-2 promulgated under the Securities Exchange Act of 1934, as amended, within
five (5) days of the date that the Company is notified (orally or in writing,
whichever is earlier) by the Commission that an Underlying Securities
Registration Statement will not be "reviewed" or is not subject to further
review or comment, or (c) a Registration Statement is not declared effective by
the Commission on or prior to the applicable Effectiveness Date, or (d) a
Registration Statement is filed with and declared effective by the Commission
but thereafter ceases to be effective at any time prior to the expiration of the
Effectiveness Period without being succeeded within 10 Business Days by a
subsequent Registration Statement filed with and declared effective by the
Commission, or (e) trading in the Common Stock shall be suspended for any reason
for more than three Trading Days (as such term is defined under the Certificate
of Vote of Directors Establishing A Series Of A Class Of Stock filed with the
State of Massachusetts in respect of the Preferred Stock (the "Certificate of
Vote")) or (f) if the conversion rights of the holders of the Preferred Stock as
set forth in the Certificate of Vote are suspended for any reason (any such
failure being referred to as an "Event," and for purposes of clauses (a), (c)
and (f) the date on which such Event occurs, or, for purposes of clause (b) the
date on which such five (5) day period is exceeded, or for purposes of clause
(d) the date which such 10 Business Day- period is exceeded, or for purposes of
clause (e) the date on which such three Trading Day period is exceeded, being
referred to as "Event Date"), then the Company shall pay the Purchaser in cash
an amount equal to 0.2% of the Purchase Price per day, payment thereof due on
the day after such Event Date and thereafter on each monthly anniversary date of
such Event Date, until such time as a subsequent Registration Statement is
declared effective by the Commission, or until any Event contemplated by clause
(e) or (f), as the case may be, is cured. If the Company fails to make any
payment required by this paragraph when due, each holder shall have the option,
exercisable by giving written notice to the Company at any time after a default
in payment and before all such defaults are cured, to require the Company to
redeem for cash all or any part of the Preferred Stock then held by that Holder
at a redemption price equal to 120% of the Purchase Price of the shares so
redeemed, provided, however that the option to require redemption shall not be
effective if the Company has been advised in writing by The Nasdaq Stock Market,
Inc. that the availability or the exercise of that option would require the
Preferred Stock to be excluded from equity of the Company for purposes of
applicable listing maintenance requirements for the Nasdaq national market
system.

               The Company shall notify each Holder within five days of each
Event and Event Date. The Company shall pay the liquidated damages due with
respect to the Registrable Securities to each Holder of record as at the Event
Date on a monthly basis, beginning with the date upon which such liquidated
damages first accrue.

      10.      Registration Expenses

               (a)   All fees and expenses incident to the performance of or
compliance with this Agreement by the Company shall be borne by the Company
whether or not the Registration Statement is filed or becomes effective and
whether or not any Registrable Securities are sold pursuant to the Registration
Statement. The fees and expenses referred to in the foregoing sentence shall
include, without limitation, (i) all registration and filing fees (including,
without limitation, fees and expenses (A) with respect to filings required to be
made with the National Association of Securities Dealers, Inc. and (B) in
compliance with state securities or Blue Sky laws (including, without
limitation, fees and disbursements of counsel for the Underwriters or Holders in
connection with Blue Sky qualifications of the


                                      -39-
   11
Registrable Securities and determination of the eligibility of the Registrable
Securities for investment under the laws of such jurisdictions as the Managing
Underwriters, if any, or Holders of a majority of Registrable Securities may
designate)), (ii) printing expenses (including, without limitation, expenses of
printing certificates for Registrable Securities and of printing prospectuses if
the printing of prospectuses is requested by the Managing Underwriters, if any,
or by the holders of a majority of the Registrable Securities included in the
Registration Statement), (iii) messenger, telephone and delivery expenses, (iv)
reasonable fees and disbursements of counsel for the Company and Special Counsel
for the Holders, (v) fees and disbursements of all independent certified public
accountants referred to in Section 3(l)(iii) (including, without limitation, the
expenses of any special audit and "cold comfort" letters required by or incident
to such performance), (vi) Securities Act liability insurance, if the Company so
desires such insurance, and (vii) fees and expenses of all other Persons
retained by the Company in connection with the consummation of the transactions
contemplated by this Agreement. In addition, the Company shall be responsible
for all of its internal expenses incurred in connection with the consummation of
the transactions contemplated by this Agreement (including, without limitation,
all salaries and expenses of its officers and employees performing legal or
accounting duties), the expense of any annual audit, the fees and expenses
incurred in connection with the listing of the Registrable Securities on any
securities exchange on which similar securities issued by the Company are then
listed.

               (b)   In connection with the Registration Statement, the Company
shall reimburse the Holders for the fees and disbursements of one firm of
attorneys chosen by the Holders of a majority of the Registrable Securities.

      11.      Indemnification. In the event any Registrable Securities are 
included in a Registration Statement under this Agreement:

               (a)   To the fullest extent permitted by law, the Company will, 
and hereby does, indemnify, hold harmless and defend each Holder who holds such
Registrable Securities, the directors, officers, partners, employees, agents of,
and each person, if any, who controls, any Holder within the meaning of the 1933
Act or the Securities Exchange Act of 1934, as amended (the "1934 Act"), and any
underwriter (as defined in the 1933 act) for the Holders, and the Directors and
officers of, and each Person, if any, who controls, any such underwriter within
the meaning of the 1933 Act or the 1934 Act (each, and "Indemnified Person"),
against any losses, claims, damages, liabilities, judgments, fines, penalties,
charges, costs, attorneys' fees, amounts paid in settlement or expenses, joint
or several, (collectively, "Claims") incurred in investigating, preparing or
defending any action, claim, suit, inquiry, proceeding, investigation or appeal
taken from the foregoing by or before any court or governmental, administrative
or other regulatory agency, body or the SEC, whether pending or threatened,
whether or not an indemnified party is or may be a party thereto ("Indemnified
Damages"), to which any of them may become subject insofar as such Claims (or
actions or proceedings, whether commenced or threatened, in respect thereof)
arise out of or are based upon: (i) any untrue statement or alleged untrue
statement of a material fact in a Registration Statement or any post-effective
amendment thereto or in any filing made in connection with the qualification of
the offering under the securities or other "blue sky" laws of any jurisdiction
in which Registrable Securities are offered ("Blue Sky Filing"), or the omission
or alleged omission to state a material fact required to be stated therein or
necessary to make the statements therein, in light of the circumstances under
which the statements therein were made, not misleading, (ii) any untrue
statement or alleged untrue statement of a material fact contained in any
preliminary prospectus if used prior to the effective date of such Registration
Statement, or contained in the final prospectus (as amended or supplemented, if
the Company files


                                      -40-
   12
any amendment thereof or supplement thereto with the SEC) or the omission or
alleged omission to state therein any material fact necessary to make the
statements made therein, in light of the circumstances under which the
statements therein were made, not misleading, or (iii) any violation or alleged
violation by the Company of the 1933 Act, the 1934 Act, any other law,
including, without limitation, any state securities law, or any rule or
regulation thereunder relating to the offer or sale of the Registrable
Securities pursuant to a Registration Statement (the matters in the foregoing
clauses (i) through (iii) being, collectively, "Violations"). Subject to the
restrictions set forth in Section 6(d) with respect to the number of legal
counsel, the Company shall reimburse the Holders and each such underwriter or
controlling person, promptly as such expenses are incurred and are due and
payable, for any legal fees or other reasonable expenses incurred by them in
connection with investigating or defending any such Claim. Notwithstanding
anything to the contrary contained herein, the indemnification agreement
contained in this Section 6(a): (i) shall not apply to a Claim arising out of or
based upon a Violation which occurs in reliance upon and in conformity with
information furnished in writing to the Company by any Indemnified Person or
underwriter for such Indemnified Person expressly for use in connection with the
preparation of the Registration Statement or any such amendment thereof or
supplement thereto, if such prospectus was timely made available by the Company
pursuant to Section 3(g); (ii) with respect to any preliminary prospectus, shall
not inure to the benefit of any such person from whom the person asserting any
such Claim purchased the Registrable Securities that are the subject thereof (or
to the benefit of any person controlling such person) if the untrue statement or
omission of material fact contained in the preliminary prospectus was corrected
in the prospectus, as then amended or supplemented, if such prospectus was
timely made available by the Company pursuant to Section 3(g), and the
Indemnified Person was promptly advised in writing not to use the incorrect
prospectus prior to the use giving rise to a violation and such Indemnified
Person, notwithstanding such advice, used it; (iii) shall not be available to
the extent such Claim is based on a failure of the Holder to deliver or to cause
to be delivered the prospectus made available by the Company; and (iv) shall not
apply to amounts paid in settlement of any Claim if such settlement is effected
without the prior written consent of the Company, which consent shall not be
unreasonably withheld. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of the Indemnified Person
and shall survive the transfer of the Registrable Securities by the Holders
pursuant to Section 8.

               (b)   In connection with any Registration Statement in which a
Holder is participating, each such Holder agrees severally and not jointly to
indemnify, hold harmless and defend, to the same extent and in the same manner
as is set forth in Section 6(a), the Company, each of its directors, each of its
officers who signs the Registration Statement, each Person, if any, who controls
the Company within the meaning of the 1933 Act or the 1934 Act (collectively and
together with an Indemnified Person, an "Indemnified Party"), against any Claim
or Indemnified Damages to which any of them may become subject, under the 1933
Act, the 1934 Act or otherwise, insofar as such Claim or Indemnified Damages
arise out of or are based upon any Violation, in each case to the extent, and
only to the extent, that such Violation occurs in reliance upon and in
conformity with written information furnished to the Company by such Holder
expressly for use in connection with such Registration Statement; and, subject
to Section 6(d), such Holder will reimburse any legal or other expenses
reasonably incurred by them in connection with investigating or defending any
such Claim; provided, however, that the indemnity agreement contained in this
Section 6(b) shall not apply to amounts paid in settlement of any Claim if such
settlement is effected without the prior written consent of such Holder, which
consent shall not be unreasonably withheld; provided, further, however, that the
Holder shall be liable under this Section 6(b) for only that amount of a Claim
or Indemnified Damages as does not exceed the net proceeds to such Holder as a
result of the sale of Registrable Securities pursuant to such


                                      -41-
   13
Registration Statement. Such indemnity shall remain in full force and effect
regardless of any investigation made by or on behalf of such Indemnified Party
and shall survive the transfer of the Registrable Securities by the Holders
pursuant to Section 8. Notwithstanding anything to the contrary contained
herein, the indemnification agreement contained in this Section 6(b) with
respect to any preliminary prospectus shall not inure to the benefit of any
Indemnified Party if the untrue statement or omission of material fact contained
in the preliminary prospectus was corrected on a timely basis in the prospectus,
as then amended or supplemented.

               (c)   The Company shall be entitled to receive indemnities from
underwriters, selling brokers, dealer managers and similar securities industry
professionals participating in any distribution, to the same extent as provided
above, with respect to information such persons so furnished in writing
expressly for inclusion in the Registration Statement.

               (d)   Promptly after receipt by an Indemnified Person or
Indemnified Party under this Section 6 of notice of the commencement of any
action or proceeding (including any governmental action or proceeding) involving
a Claim, such Indemnified Person or Indemnified Party shall, if a Claim in
respect thereof is to be made against any indemnifying party under this Section
6, deliver to the indemnifying party a written notice of the commencement
thereof, and the indemnifying party shall have the right to participate in, and,
to the extent the indemnifying party so desires, jointly with any other
indemnifying party similarly noticed, to assume control of the defense thereof
with counsel mutually satisfactory to the indemnifying party and the Indemnified
Person or the Indemnified Party, as the case may be; provided, however, that an
Indemnified Person or the Indemnified Party shall have the right to retain its
own counsel with the fees and expenses to be paid by the indemnifying party, if,
in the reasonable opinion of counsel retained by the indemnifying party, the
representation by such counsel of the Indemnified Person or Indemnified Party
and the indemnifying party would be inappropriate due to actual or potential
differing interests between such proceeding. The Company shall pay reasonable
fees for only one separate legal counsel for the Holders, and such legal counsel
shall be selected by the Holders holding a majority in interest of the
Registrable Securities included in the Registration Statement to which the Claim
relates. The Indemnified Party or Indemnified Person shall cooperate fully with
the indemnifying party in connection with any negotiation or defense of any such
action or claim by the indemnifying party all information reasonably available
to the Indemnified Party or Indemnified Person which relates to such action or
claim. The indemnifying party shall keep the Indemnified Party or Indemnified
Person fully apprised at all times as to the status of the defense or any
settlement negotiations with respect thereto. No indemnifying party shall be
liable for any settlement of any action, claim or proceeding effected without
its written consent, provided, however, that the indemnifying party shall not
unreasonably withhold, delay or condition its consent. No indemnifying party
shall, without the consent of the Indemnified Party or Indemnified Person,
consent to entry of any judgment or enter into any settlement or other
compromise which does not include as an unconditional term thereof the giving by
the claimant or plaintiff to such Indemnified party or Indemnified Person of a
release from all liability in respect to such claim or litigation. Following
indemnification as provided for hereunder, the indemnifying party shall be
subrogated to all rights of the Indemnified Party or Indemnified Person with
respect to all third parties, firms or corporations relating to the matter for
which indemnification has been made. The failure to deliver written notice to
the indemnifying party within a reasonable time of the commencement of any such
action shall not relieve such indemnifying party of any liability to the
Indemnified Person or Indemnified Party under this Section 6, except to the
extent that the indemnifying party is prejudiced in its ability to defend such
action.


                                      -42-
   14
               (e)   The indemnification required by this Section 6 shall be 
made by periodic payments of the amount thereof during the course of the
investigation or defense, as when bills are received or Indemnified Damages are
incurred.

               (f)   The indemnity agreements contained herein shall be in
addition to (i) any cause of action or similar right of the Indemnified party or
Indemnified Person against the indemnifying party or others, and (ii) any
liabilities the indemnifying party may be subject to pursuant to the law.

               (g)   Contribution. To the extent any indemnification by an
indemnifying party is prohibited or limited by law, the indemnifying party
agrees to make the maximum contribution with respect to any amounts for which it
would otherwise be liable under Section 6 to the fullest extent permitted by
law; provided, however, that: (i) no contribution shall be made under
circumstances where the maker would not have been liable for indemnification
under the fault standards set forth in Section 6; (ii) no seller of Registrable
Securities guilty of fraudulent misrepresentation (within the meaning of Section
11(f) of the 1933 Act) shall be entitled to contribution from any seller of
Registrable Securities who was not guilty of fraudulent misrepresentation; and
(iii) contribution by any seller of Registrable Securities shall be limited in
amount to the net amount of proceeds received by such seller from the sale of
such Registrable Securities.

      12.      Rule 144

               The Company shall file the reports required to be filed by it
under the Securities Act and the Exchange Act in a timely manner and, if at any
time the Company is not required to file such reports, they will, upon the
request of any Holder, make publicly available other information so long as
necessary to permit sales of its securities pursuant to Rule 144. The Company
further covenants that it will take such further action as any Holder may
reasonably request, all to the extent required from time to time to enable such
Holder to sell Registrable Securities without registration under the Securities
Act within the limitation of the exemptions provided by Rule 144. Upon the
request of any Holder, the Company shall deliver to such Holder a written
certification of a duly authorized officer as to whether it has complied with
such requirements.

      13.      Miscellaneous

               (a)   Remedies. In the event of a breach by the Company or by a
Holder, of any of their obligations under this Agreement, each Holder or the
Company, as the case may be, in addition to being entitled to exercise all
rights granted by law and under this Agreement, including recovery of damages,
will be entitled to specific performance of its rights under this Agreement. The
Company and each Holder agree that monetary damages would not provide adequate
compensation for any losses incurred by reason of a breach by it of any of the
provisions of this Agreement and hereby further agrees that, in the event of any
action for specific performance in respect of such breach, it shall waive the
defense that a remedy at law would be adequate.

               (b)   No Inconsistent Agreements. Except as set forth in 
Schedule 8 hereto, neither the Company nor any of its subsidiaries has, as of
the date hereof, nor shall the Company or any of its subsidiaries, on or after
the date of this Agreement, enter into any agreement with respect to its
securities that is inconsistent with the rights granted to the


                                      -43-
   15
Holders in this Agreement or otherwise conflicts with the provisions hereof.
Neither the Company nor any of its subsidiaries has previously entered into any
agreement granting any registration rights with respect to any of its securities
to any Person. Without limiting the generality of the foregoing, without the
written consent of the Holders of a majority of the then outstanding Registrable
Securities, the Company shall not grant to any Person the right to request the
Company to register any securities of the Company under the Securities Act
unless the rights so granted are subject in all respects to the prior rights in
full of the Holders set forth herein, and are not otherwise in conflict or
inconsistent with the provisions of this Agreement.

               (c)   No Piggyback on Registrations. Except as set forth in
Schedule 8 hereto, neither of the Company nor any of its security holders (other
than the Holders in such capacity pursuant hereto) may include securities of the
Company in the Registration Statement other than the Common Stock to be issued
under the Purchase Agreement, and the Company shall not enter into any agreement
providing any such right to any of its securityholders.

               (d)   Piggy-Back Registrations. If at any time the Company shall
determine to prepare and file with the Commission a registration statement
relating to an offering for its own account or the account of others under the
Securities Act of any of its equity securities, other than on Form S-4 or Form
S-8 (each as promulgated under the Securities Act) or their then equivalents
relating to equity securities to be issued solely in connection with any
acquisition of any entity or business or equity securities issuable in
connection with stock option or other employee benefit plans, the Company shall
send to each holder of Registrable Securities written notice of such
determination and, if within twenty (20) days after receipt of such notice, any
such holder shall so request in writing, the Company shall include in such
registration statement all or any part of the Registrable Securities such holder
requests to be registered, except that if, in connection with any Underwritten
Offering for the account of the Company the managing underwriter(s) thereof
shall impose a limitation on the number of shares of Common Stock which may be
included in the registration statement because, in such underwriter(s)'
judgment, such limitation is necessary to effect an orderly public distribution
of securities covered thereby, then the Company shall be obligated to include in
such registration statement only such limited portion of the Registrable
Securities for to which such holder has requested inclusion hereunder. Any
exclusion of Registrable Securities shall be made pro rata among the holders
seeking to include Registrable Securities, in proportion to the number of
Registrable Securities sought to be included by such holders; provided, however,
that the Company shall not exclude any Registrable Securities unless the Company
has first excluded all outstanding securities the holders of which are not
entitled by right to inclusion of securities in such registration statement; and
provided, further, however, that, after giving effect to the immediately
preceding proviso, any exclusion of Registrable Securities shall be made pro
rata with holders of other securities having the right to include such
securities in such registration statement. No right to registration of
Registrable Securities under this Section shall be construed to limit any
registration otherwise required hereunder. This Section 8(d) shall apply only at
such times when all of the Registrable Securities issued and outstanding cannot
be sold pursuant to an effective Registration Statement on Form S-3 and for a
period not to exceed two years after the date of this Agreement.

               (e)   Amendments and Waivers. The provisions of this Agreement,
including the provisions of this sentence, may not be amended, modified or
supplemented, and waivers or consents to departures from the provisions hereof
may not be given, unless the same shall be in writing and signed by the Company
and the Holders of at least a majority of the then outstanding Registrable
Securities; provided, however, that, for the purposes of this sentence,


                                      -44-
   16
Registrable Securities that are owned, directly or indirectly, by the Company,
or an Affiliate of the Company are not deemed outstanding. Notwithstanding the
foregoing, a waiver or consent to depart from the provisions hereof with respect
to a matter that relates exclusively to the rights of Holders and that does not
directly or indirectly affect the rights of other Holders may be given by
Holders of at least a majority of the Registrable Securities to which such
waiver or consent relates; provided, however, that the provisions of this
sentence may not be amended, modified, or supplemented except in accordance with
the provisions of the immediately preceding sentence.

               (f)   Notices. Any and all notices or other communications or
deliveries required or permitted to be provided hereunder shall be in writing
and shall be deemed given and effective on the earliest of (i) the date of
transmission, if such notice or communication is delivered via facsimile at the
facsimile telephone number specified in this Section prior to 4:30 p.m. (Eastern
Time) on a Business Day, (ii) the Business Day after the date of transmission,
if such notice or communication is delivered via facsimile at the facsimile
telephone number specified in the Purchase Agreement later than 4:30 p.m.
(Eastern Time) on any date and earlier than 11:59 p.m. (Eastern Time) on such
date, (iii) the Business Day following the date of mailing, if sent by
nationally recognized overnight courier service, or (iv) upon actual receipt by
the party to whom such notice is required to be given. The address for such
communications shall be:



               If to the Company:   Cayenne Software, Inc.
                                    8 New England Executive Park
                                    Burlington, MA 01803
                                    Facsimile No.: (617) 229-8124
                                    Attention: Frederick H. Phillips

               With copies to:      Foley, Hoag & Eliot LLP
                                    One Post Office Square
                                    Boston, MA 02109
                                    Facsimile No.: (617) 832-7000
                                    Attention: David W. Walker

               If to any Purchaser: to the address stated for that Purchaser in
                                    Schedule A, with a copy to the respective
                                    person so specified in that Schedule,

               If to any other Person who is then the registered Holder:

                                    To the address of such Holder as it appears 
                                    in the stock transfer books of the Company

or such other address as may be designated in writing hereafter, in the same
manner, by such Person.

               (g)   Successors and Assigns. This Agreement shall inure to the
benefit of and be binding upon the successors and permitted assigns of each of
the parties and shall inure to the benefit of each Holder. The Company may not
assign its rights or obligations hereunder


                                      -45-
   17
without the prior written consent of each Holder. A Holder may assign its rights
hereunder in the manner and to the Persons as permitted under the Purchase
Agreement.

               (h)   Assignment of Registration Rights. The rights of the
Purchaser hereunder, including the right to have the Company register for resale
Registrable Securities in accordance with the terms of this Agreement, shall be
automatically assignable by the Purchaser to any assignee or transferee of all
or a portion of the shares of Preferred Stock, the Warrants or the Registrable
Securities if: (i) the Purchaser agrees in writing with the transferee or
assignee to assign such rights, and a copy of such agreement is furnished to the
Company within a reasonable time after such assignment, (ii) the Company is,
within a reasonable time after such transfer or assignment, furnished with
written notice of (a) the name and address of such transferee or assignee, and
(b) the securities with respect to such registration rights are being
transferred or assigned, (iii) following such transfer or assignment the further
disposition of such securities by the transferee or assignees restricted under
the Securities Act and applicable state securities laws, (iv) at or before the
time the Company receives the written notice contemplated by clause (ii) of this
Section, the transferee or assignee agrees in writing with the Company to be
bound by all of the provisions of this Agreement, and (v) such transfer shall
have been made in accordance with the applicable requirements of the Purchase
Agreement. The rights to assignment shall apply to the Purchaser's (and to
subsequent) successors and assigns.

               (i)   Counterparts. This Agreement may be executed in any number
of counterparts, each of which when so executed shall be deemed to be an
original and, all of which taken together shall constitute one and the same
Agreement. In the event that any signature is delivered by facsimile
transmission, such signature shall create a valid binding obligation of the
party executing (or on whose behalf such signature is executed) the same with
the same force and effect as if such facsimile signature were the original
thereof.

               (j)   Governing Law; Arbitration;. (A) This Agreement shall be
governed by and construed and enforced in accordance with the internal laws of
NewYork, without regard to principles of conflicts of law thereof.

                     (B) All disputes between the parties hereto arising under 
the terms of this Agreement shall be arbitrated in New York City under the rules
of the American Arbitration Association then in effect in that city. Judgment on
any award made by the arbitrators hereunder may be rendered in any court having
jurisdiction. The parties consent to the nonexclusive jurisdiction of the United
States District Court sitting in the city where the arbitration was conducted,
in connection with the enforcement of such award. The parties agree to keep
confidential any materials, documents or other information that is disclosed in
connection with any arbitration proceeding.

               (k)   Cumulative Remedies. The remedies provided herein are
cumulative and not exclusive of any remedies provided by law.

               (l)   Severability. If any term, provision, covenant or
restriction of this Agreement is held by a court of competent jurisdiction to be
invalid, illegal, void or unenforceable, the remainder of the terms, provisions,
covenants and restrictions set forth herein shall remain in full force and
effect and shall in no way be affected, impaired or invalidated, and the parties
hereto shall use their reasonable efforts to find and employ an alternative
means to achieve the same or substantially the same result as that contemplated
by


                                      -46-
   18
such term, provision, covenant or restriction. It is hereby stipulated and
declared to be the intention of the parties that they would have executed the
remaining terms, provisions, cove nants and restrictions without including any
of such that may be hereafter declared invalid, illegal, void or unenforceable.

               (m)   Headings. The headings in this Agreement are for
convenience of reference only and shall not limit or otherwise affect the
meaning hereof.

               (n)   Shares Held by The Company and its Affiliates. Whenever the
consent or approval of Holders of a specified percentage of Registrable
Securities is required hereunder, Registrable Securities held by the Company or
its Affiliates (other than the Purchaser or transferees or successors or assigns
thereof if such Persons are deemed to be Affiliates solely by reason of their
holdings of such Registrable Securities) shall not be counted in determining
whether such consent or approval was given by the Holders of such required
percentage.

                  [REMAINDER OF PAGE INTENTIONALLY LEFT BLANK]

                            [SIGNATURE PAGE FOLLOWS]


                                      -47-
   19
               IN WITNESS WHEREOF, the parties have executed this Agreement as
of the date first written above.

                               CAYENNE SOFTWARE, INC.


                               By:______________________________________________
                                  Name: Frederick H. Phillips
                                  Title: Vice President and Treasurer


                               INTEGRAL CAPITAL
                               PARTNERS III, L.P.



                               By:______________________________________________
                                  Name:
                                  Title:


                               INTEGRAL CAPITAL PARTNERS
                               INTERNATIONAL III, L.P.



                               By:______________________________________________
                                  Name:
                                  Title:


                               THEMIS PARTNERS, L.P.
                                  By:    Promethean Investment Group,
                                         L.L.C.
                                  Its:   General Partner



                               By:______________________________________________
                                  Name: Brian S. Yeh
                                  Its: Authorized Representative

                               HERACLES FUND
                                  By:    Promethean Investment Group,
                                         L.L.C.
                                  Its:   Investment Advisor



                                      -48-
   20
                               By:______________________________________________
                                  Name: Brian S. Yeh
                                  Its: Authorized Representative


                               LEWIS A. FRASER
                                  By:    Promethean Investment Group,
                                         L.L.C.
                                  Its:   Investment Advisor



                               By:______________________________________________
                                  Name: Brian S. Yeh
                                  Its: Authorized Representative


                               QUISSETT PARTNERS, L.P.
                                  By:   Wellington Management Company,
                                         LP
                                  Its:   Investment Adviser



                               By:______________________________________________
                                  Name:
                                  Title:

                               QUISSETT INVESTORS (BERMUDA)
                               LP
                                  By:   Wellington Management Company,
                                         LP
                                  Its:   Investment Adviser



                               By:______________________________________________
                                  Name:
                                  Title:



                               WINSTON I



                               By:______________________________________________
                                  Name:
                                  Title:



                                      -49-
   21
                               WINSTON II LLC
                                  By:    Chatterjee Advisors LLC
                                  Its:   Manager


                               By:______________________________________________
                                  Name:
                                  Title:



                               WINSTON II LDC


                               By:______________________________________________
                                  Name:
                                  Title:



                                      -50-