<PAGE>

                                                                     EXHIBIT 4.3

THE SECURITIES REPRESENTED BY THIS CERTIFICATE HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AND HAVE BEEN ACQUIRED FOR INVESTMENT AND NOT WITH A
VIEW TO, OR IN CONNECTION WITH, THE SALE OR DISTRIBUTION THEREOF. NO SUCH SALE
OR DISTRIBUTION MAY BE EFFECTED WITHOUT AN EFFECTIVE REGISTRATION STATEMENT
RELATED THERETO OR AN OPINION OF COUNSEL IN A FORM SATISFACTORY TO THE COMPANY
THAT SUCH REGISTRATION IS NOT REQUIRED UNDER THE SECURITIES ACT OF 1933.

Warrant No. W-CS-2                                    Number of Shares:  50,000
Date of Issuance:  October 18, 2002                     (subject to adjustment)

                           PERSISTENCE SOFTWARE, INC.

                              COMMON STOCK WARRANT
                              --------------------

         Persistence Software, Inc. (the "COMPANY"), for value received equal to
$0.001 per share issuable hereunder, hereby certifies that RTX SECURITIES
CORPORATION, or its registered assigns (the "REGISTERED HOLDER"), is entitled,
subject to the terms set forth below, to purchase from the Company, at any time
after the date hereof and on or before the Expiration Date (as defined in
Section 5 below), up to 50,000 shares (as adjusted from time to time pursuant to
the provisions of this Warrant) of Common Stock of the Company, at a per share
purchase price equal to $0.38, the closing sale price of the Company's Common
Stock on the date hereof. The shares purchasable upon exercise of this Warrant
and the purchase price per share, as adjusted from time to time pursuant to the
provisions of this Warrant, are hereinafter referred to as the "WARRANT STOCK"
and the "PURCHASE PRICE," respectively.

         This Warrant is issued pursuant to that certain Advisory Agreement,
dated as of September 27, 2002, between the Company and RTX Securities
Corporation (the "ADVISORY AGREEMENT") and is subject to the terms and
conditions of the Advisory Agreement.

         1. FULLY VESTED SHARES. The shares of Warrant Stock are fully vested
and exercisable as of the date of this Warrant.

         2. EXERCISE.

                  (a) METHOD OF EXERCISE. This Warrant may be exercised by the
Registered Holder, in whole or in part, in accordance with the foregoing
schedule, by surrendering this Warrant, with the purchase/exercise form appended
hereto as EXHIBIT A duly executed by such Registered Holder or by such
Registered Holder's duly authorized attorney, at the principal office of the
Company, or at such other office or agency as the Company may designate,
accompanied by payment in full of the Purchase Price payable in respect of the
number of shares of Warrant Stock purchased upon such exercise. The Purchase
Price may be paid by cash, check, wire transfer or by the surrender of
promissory notes or other instruments representing indebtedness of the Company
to the Registered Holder.

                  (b) EFFECTIVE TIME OF EXERCISE. Each exercise of this Warrant
shall be deemed to have been effected immediately prior to the close of business
on the day on which this Warrant shall have been surrendered to the Company as
provided in Section 2(a) above. At such time, the person or persons in whose
name or names any certificates for Warrant Stock shall be issuable upon such
exercise as provided in Section 2(c) below shall be deemed to have become the
holder or holders of record of the Warrant Stock represented by such
certificates.

<PAGE>

                  (c) NET ISSUE EXERCISE.

                           (i) In lieu of exercising this Warrant in the manner
provided above in Section 2(a), the Registered Holder may elect to receive
shares equal to the value of this Warrant (or the portion thereof being
canceled) by surrender of this Warrant at the principal office of the Company
together with notice of such election on the purchase/exercise form appended
hereto as EXHIBIT A duly executed by such Registered Holder or such Registered
Holder's duly authorized attorney, in which event the Company shall issue to
holder a number of shares of Common Stock computed using the following formula:

                                    X =     Y (A - B)
                                            ---------
                                                A

Where             X =   The number of shares of Common Stock to be issued to the
                        Registered Holder.

                  Y =   The number of shares of Common Stock purchasable
                        under this Warrant (at the date of such calculation).

                  A =   The fair market value of one share of Common
                        Stock (at the date of such calculation). B = The
                        Purchase Price (as adjusted to the date of such
                        calculation).

                           (ii) For purposes of this Section 2(c), the fair
market value of one share of Common Stock on the date of calculation shall mean,

                                (1) if the Company's Common Stock is traded on
the Nasdaq stock market, the average of the closing sales prices over a thirty
(30) day period ending three days before date of calculation; or

                                (2) if the Company's Common Stock is actively
traded over-the-counter, the fair market value shall be deemed to be the average
of the closing bid or sales price (whichever is applicable) over the thirty (30)
day period ending three days before the date of calculation.

                  (d) DELIVERY TO HOLDER. As soon as practicable after the
exercise of this Warrant in whole or in part, and in any event within 10 days
thereafter, the Company at its expense will cause to be issued in the name of,
and delivered to, the Registered Holder, or as such Holder (upon payment by such
Holder of any applicable transfer taxes) may direct:

                           (i) a certificate or certificates for the number of
shares of Warrant Stock to which such Registered Holder shall be entitled, and

                           (ii) in case such exercise is in part only, a new
warrant or warrants (dated the date hereof) of like tenor, calling in the
aggregate on the face or faces thereof for the number of shares of Warrant Stock
equal (without giving effect to any adjustment therein) to the number of such
shares called for on the face of this Warrant minus the number of such shares
purchased by the Registered Holder upon such exercise as provided in Section
2(a) above.

                                      -2-
<PAGE>

         3. ADJUSTMENTS.

                  (a) STOCK SPLITS AND DIVIDENDS. If outstanding shares of the
Company's Common Stock shall be subdivided into a greater number of shares or a
dividend in Common Stock shall be paid in respect of Common Stock, the Purchase
Price in effect immediately prior to such subdivision or at the record date of
such dividend shall simultaneously with the effectiveness of such subdivision or
immediately after the record date of such dividend be proportionately reduced.
If outstanding shares of Common Stock shall be combined into a smaller number of
shares, the Purchase Price in effect immediately prior to such combination
shall, simultaneously with the effectiveness of such combination, be
proportionately increased. When any adjustment is required to be made in the
Purchase Price, the number of shares of Warrant Stock purchasable upon the
exercise of this Warrant shall be changed to the number determined by dividing
(i) an amount equal to the number of shares issuable upon the exercise of this
Warrant immediately prior to such adjustment, multiplied by the Purchase Price
in effect immediately prior to such adjustment, by (ii) the Purchase Price in
effect immediately after such adjustment.

                  (b) RECLASSIFICATION, ETC. In case of any reclassification or
change of the outstanding securities of the Company or of any reorganization of
the Company (or any other corporation the stock or securities of which are at
the time receivable upon the exercise of this Warrant) or any similar corporate
reorganization on or after the date hereof, then and in each such case the
holder of this Warrant, upon the exercise hereof at any time after the
consummation of such reclassification, change or reorganization shall be
entitled to receive, in lieu of the stock or other securities and property
receivable upon the exercise hereof prior to such consummation, the stock or
other securities or property to which such holder would have been entitled upon
such consummation if such holder had exercised this Warrant immediately prior
thereto, all subject to further adjustment as provided in Section 3(a); and in
each such case, the terms of this Section 3 shall be applicable to the shares of
stock or other securities properly receivable upon the exercise of this Warrant
after such consummation.

                  (c) ADJUSTMENT CERTIFICATE. When any adjustment is required to
be made in the Warrant Stock or the Purchase Price pursuant to this Section 3,
the Company shall promptly mail to the Registered Holder a certificate setting
forth (i) a brief statement of the facts requiring such adjustment, (ii) the
Purchase Price after such adjustment and (iii) the kind and amount of stock or
other securities or property into which this Warrant shall be exercisable after
such adjustment.

         4. TRANSFERS.

                  (a) UNREGISTERED SECURITY. Each holder of this Warrant
acknowledges that this Warrant and the Warrant Stock have not been registered
under the Securities Act of 1933, as amended (the "SECURITIES ACT"), and agrees
not to sell, pledge, distribute, offer for sale, transfer or otherwise dispose
of this Warrant or any Warrant Stock issued upon its exercise in the absence of
(i) an effective registration statement under the Act as to this Warrant or such
Warrant Stock and registration or qualification of this Warrant or such Warrant
Stock under any applicable U.S. federal or state securities law then in effect
or (ii) an opinion of counsel, reasonably satisfactory to the Company, that such
registration and qualification are not required. Each certificate or other
instrument for Warrant Stock issued upon the exercise of this Warrant shall bear
a legend substantially to the foregoing effect.

                  (b) TRANSFERABILITY. Subject to the provisions of Section 4(a)
hereof, this Warrant and all rights hereunder are transferable, in whole or in
part, upon surrender of the Warrant with a properly executed assignment (in the
form of EXHIBIT B hereto) at the principal office of the Company PROVIDED,
HOWEVER, that this Warrant may not be transferred in part unless the transferee
acquires the right to purchase at least 25,000 shares (as adjusted pursuant to
Section 2) of Warrant Stock hereunder.

                                      -3-
<PAGE>

                  (c) WARRANT REGISTER. The Company will maintain a register
containing the names and addresses of the Registered Holders of this Warrant.
Until any transfer of this Warrant is made in the warrant register, the Company
may treat the Registered Holder of this Warrant as the absolute owner hereof for
all purposes; PROVIDED, HOWEVER, that if this Warrant is properly assigned in
blank, the Company may (but shall not be required to) treat the bearer hereof as
the absolute owner hereof for all purposes, notwithstanding any notice to the
contrary. Any Registered Holder may change such Registered Holder's address as
shown on the warrant register by written notice to the Company requesting such
change.

         5. NO IMPAIRMENT. The Company will not, by amendment of its charter or
through reorganization, consolidation, merger, dissolution, sale of assets or
any other voluntary action, avoid or seek to avoid the observance or performance
of any of the terms of this Warrant, but will (subject to Section 14 below) at
all times in good faith assist in the carrying out of all such terms and in the
taking of all such action as may be necessary or appropriate in order to protect
the rights of the holder of this Warrant against impairment.

         6. TERMINATION. This Warrant (and the right to purchase securities upon
exercise hereof) shall terminate on the earlier of October 18, 2007 or the
closing of any sale of all or substantially all of the assets of the Company, or
any merger, consolidation or any other transaction or series of related
transactions in which the Company's stockholders immediately prior thereto own
less than a majority of the voting stock of the Company (or its successor or
parent) immediately thereafter (the "EXPIRATION DATE").

         7. NOTICES OF CERTAIN TRANSACTIONS. In case:

                  (a) the Company shall take a record of the holders of its
Common Stock (or other stock or securities at the time deliverable upon the
exercise of this Warrant) for the purpose of entitling or enabling them to
receive any dividend or other distribution, or to receive any right to subscribe
for or purchase any shares of stock of any class or any other securities, or to
receive any other right, to subscribe for or purchase any shares of stock of any
class or any other securities, or to receive any other right, or

                  (b) of any capital reorganization of the Company, any
reclassification of the capital stock of the Company, any consolidation or
merger of the Company, any consolidation or merger of the Company with or into
another corporation (other than a consolidation or merger in which the Company
is the surviving entity), or any transfer of all or substantially all of the
assets of the Company, or

                  (c) of the voluntary or involuntary dissolution, liquidation
or winding-up of the Company,

then, and in each such case, the Company will mail or cause to be mailed to the
Registered Holder of this Warrant a notice specifying, as the case may be, (i)
the date on which a record is to be taken for the purpose of such dividend,
distribution or right, and stating the amount and character of such dividend,
distribution or right, or (ii) the effective date on which such reorganization,
reclassification, consolidation, merger, transfer, dissolution, liquidation or
winding-up is to take place, and the time, if any is to be fixed, as of which
the holders of record of Common Stock (or such other stock or securities at the
time deliverable upon such reorganization, reclassification, consolidation,
merger, transfer, dissolution, liquidation or winding-up) are to be determined.

                                      -4-
<PAGE>

         8. RESERVATION OF STOCK. The Company will at all times reserve and keep
available, solely for the issuance and delivery upon the exercise of this
Warrant, such shares of Warrant Stock and other stock, securities and property,
as from time to time shall be issuable upon the exercise of this Warrant.

         9. EXCHANGE OF WARRANTS. Upon the surrender by the Registered Holder of
any Warrant or Warrants, properly endorsed, to the Company at the principal
office of the Company, the Company will, subject to the provisions of Section 4
hereof, issue and deliver to or upon the order of such Holder, at the Company's
expense, a new Warrant or Warrants of like tenor, in the name of such Registered
Holder or as such Registered Holder (upon payment by such Registered Holder of
any applicable transfer taxes) may direct, calling in the aggregate on the face
or faces thereof for the number of shares of Common Stock called for on the face
or faces of the Warrant or Warrants so surrendered.

         10. REPLACEMENT OF WARRANTS. Upon receipt of evidence reasonably
satisfactory to the Company of the loss, theft, destruction or mutilation of
this Warrant and (in the case of loss, theft or destruction) upon delivery of an
indemnity agreement (with surety if reasonably required) in an amount reasonably
satisfactory to the Company, or (in the case of mutilation) upon surrender and
cancellation of this Warrant, the Company will issue, in lieu thereof, a new
Warrant of like tenor.

         11. NOTICES. Any notice required or permitted by this Warrant shall be
in writing and shall be deemed sufficient upon receipt, when delivered
personally or by courier, overnight delivery service or confirmed facsimile, or
48 hours after being deposited in the regular mail as certified or registered
mail (airmail if sent internationally) with postage prepaid, addressed (a) if to
the Registered Holder, to the address of the Registered Holder most recently
furnished in writing to the Company and (b) if to the Company, to the address
set forth below or subsequently modified by written notice to the Registered
Holder.

         12. NO RIGHTS AS STOCKHOLDER. Until the exercise of this Warrant, the
Registered Holder of this Warrant shall not have or exercise any rights by
virtue hereof as a stockholder of the Company.

         13. NO FRACTIONAL SHARES. No fractional shares of Common Stock will be
issued in connection with any exercise hereunder. In lieu of any fractional
shares which would otherwise be issuable, the Company shall pay cash equal to
the product of such fraction multiplied by the fair market value of one share of
Common Stock on the date of exercise, as determined in good faith by the
Company's Board of Directors.

         14. AMENDMENT OR WAIVER. Any term of this Warrant may be amended or
waived upon written consent of the Company and the Registered Holder.

         15. HEADINGS. The headings in this Warrant are for purposes of
reference only and shall not limit or otherwise affect the meaning of any
provision of this Warrant.

         16. GOVERNING LAW. This Warrant shall be governed, construed and
interpreted in accordance with the laws of the State of Delaware, without giving
effect to principles of conflicts of law.

         17. REGISTRATION RIGHTS. The Warrant Shares are subject to the re-sale
registration rights described in the Registration Rights Agreement by and
between the Company and RTX Securities Corporation and dated concurrently
herewith.

                                      -5-
<PAGE>

         18. REPRESENTATIONS AND COVENANTS OF THE HOLDER. This Warrant has been
entered into by the Company in reliance upon the following representations and
covenants of the Registered Holder:

                   (a) INVESTMENT PURPOSE. The Warrant and the Common Stock
issuable upon exercise of the Warrant will be acquired for investment and not
with a view to the sale or distribution of any part thereof, and the Holder has
no present intention of selling or engaging in any public distribution of the
same except pursuant to a registration or exemption pursuant to the Securities
Act.

                   (b) PRIVATE ISSUE. The Registered Holder understands (i) that
neither the Warrant nor the Common Stock issuable upon exercise of this Warrant
is registered under the Securities Act or qualified under applicable state
securities laws on the ground that the issuance contemplated by this Warrant
will be exempt from the registration and qualifications requirements thereof
pursuant to Section 4(2) of the Securities Act and any applicable state
securities laws, and (ii) that the Company's reliance on such exemption is
predicated on the representations set forth in this Section 18.

                   (c) DISPOSITION OF HOLDER'S RIGHTS. In no event will the
Registered Holder make a disposition of the Warrant or the Common Stock issuable
upon exercise of the Warrant unless and until (i) it shall have notified the
Company of the proposed disposition, and (ii) if requested by the Company, it
shall have furnished the Company with an opinion of counsel satisfactory to the
Company and its counsel to the effect that (A) appropriate action necessary for
compliance with the Securities Act has been taken, or (B) an exemption from the
registration requirements of the Securities Act is available. Notwithstanding
the foregoing, the restrictions imposed upon the transferability of any of its
rights to acquire Common Stock or Common Stock issuable on the exercise of such
rights do not apply to transfers from the beneficial owner of any of the
aforementioned securities to its nominee or from such nominee to its beneficial
owner, and shall terminate as to any particular share of Common Stock when (1)
such security shall have been effectively registered under the Securities Act
and sold by the holder thereof in accordance with such registration or (2) such
security shall have been sold without registration in compliance with Rule 144
under the Securities Act, or (3) a letter shall have been issued to the
Registered Holder at its request by the staff of the Securities and Exchange
Commission (the "SEC") or a ruling shall have been issued to the Registered
Holder at its request by the SEC stating that no action shall be recommended by
such staff or taken by SEC, as the case may be, if such security is transferred
without registration under the Securities Act in accordance with the conditions
set forth in such letter or ruling and such letter or ruling specifies that no
subsequent restrictions on transfer are required. Whenever the restrictions
imposed hereunder shall terminate, as hereinabove provided, the Registered
Holder or holder of a share of Common Stock then outstanding as to which such
restrictions have terminated shall be entitled to receive from the Company,
without expense to such holder, one or more new certificates for the Warrant or
for such shares of Common Stock not bearing any restrictive legend.

                   (d) FINANCIAL RISK. The Registered Holder has such knowledge
and experience in financial and business matters as to be capable of evaluating
the merits and risks of its investment, and has the ability to bear the economic
risks of its investment.

                   (e) RISK OF NO REGISTRATION. The Registered Holder
understands that if the Company does not register with the SEC pursuant to
Section 12 of the Securities Act, or file reports pursuant to Section 15(d), of
the Securities Exchange Act of 1934 (the "EXCHANGE ACT"), or if a registration
statement covering the securities under the Securities Act is not in effect when
the Registered Holder desires to sell the Common Stock issuable upon exercise of


                                      -6-
<PAGE>

the Warrant, it may be required to hold such securities for an indefinite
period. The Registered Holder also understands that any sale of the Warrant or
the Common Stock issuable upon exercise of the Warrant which might be made by it
in reliance upon Rule 144 under the Securities Act may be made only in
accordance with the terms and conditions of that Rule.

                  (f) ACCREDITED INVESTOR. The Registered Holder is an
"accredited investor" within the meaning of Rule 501 of Regulation D under the
Securities Act, as presently in effect.


                                      -7-
<PAGE>


         IN WITNESS WHEREOF, the parties have executed this Common Stock Warrant
as of the date first above written.


                                    PERSISTENCE SOFTWARE, INC.


                                    By: /s/ Christine Russell
                                        -------------------------------
                                    Title: Chief Financial Officer

                                    Address: Persistence Software Inc.
                                             1720 S. Amphlett Blvd, 3rd Floor
                                             San Mateo, CA 94402
                                             Attention:  Chief Financial Officer

                                    Fax Number: (650) 341-8432


AGREED TO AND ACCEPTED BY:

RTX SECURITIES CORPORATION

By:  /s/ Gregory S. Curhan
     ----------------------
Title:  President

Address: 100 Pine Street
           San Francisco, CA 94111

Fax Number: (415) 274-5669


                                      -8-
<PAGE>

                                    EXHIBIT A
                                    ---------

                             PURCHASE/EXERCISE FORM
                             ----------------------


To:      Persistence Software, Inc.                                   Dated:

         The undersigned, pursuant to the provisions set forth in the attached
Warrant No. W-CS-2, hereby irrevocably elects to purchase _______ shares of the
Common Stock covered by such Warrant and herewith makes payment of $_________,
representing the full purchase price for such shares at the price per share
provided for in such Warrant.



         The undersigned acknowledges that it has reviewed the representations
and warranties contained in Section 18 of the Warrant and by its signature below
hereby makes such representations and warranties to the Company. Defined terms
contained in such representations and warranties shall have the meanings
assigned to them in the Warrant.

                                   Signature:  _________________________________

                                   Name (print):  ______________________________

                                   Title (if applic.):  ________________________

                                   Company (if applic.):  ______________________


<PAGE>


                                    EXHIBIT B
                                    ---------

                                 ASSIGNMENT FORM
                                 ---------------

         FOR VALUE RECEIVED, _________________________________________ hereby
sells, assigns and transfers all of the rights of the undersigned under the
attached Warrant with respect to the number of shares of Common Stock covered
thereby set forth below, unto:

<TABLE>
<CAPTION>

             NAME OF ASSIGNEE                          ADDRESS/FAX NUMBER                    NO. OF SHARES
             ----------------                          ------------------                    -------------
<S>          <C>                                       <C>                                   <C>




</TABLE>


Dated:                                Signature:
      -----------------------------               ------------------------------

                                                  ------------------------------


                                      Witness:
                                                  ------------------------------


<PAGE>



                                    EXHIBIT C
                                    ---------

                          REGISTRATION RIGHTS AGREEMENT
                          -----------------------------