EXHIBIT 5.1

                               CONSENT OF COUNSEL

December 22, 2003

Persistence Software, Inc.
1720 South Amphlett Blvd., Third Floor
San Mateo, California 94402

Registration Statement on Form S-3
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Ladies and Gentlemen:


         We have examined the Registration Statement on Form S-3 (the
"REGISTRATION STATEMENT") filed by you with the Securities and Exchange
Commission (the "COMMISSION") on or about December 22, 2003 in connection with
the registration under the Securities Act of 1933, as amended, of 675,869 shares
of your currently issued and outstanding common stock (the "Shares") and
warrants to purchase 223,513 shares of common stock (the "Warrant Shares"), sold
to certain stockholders listed in the Registration Statement (the "Selling
Stockholders"). As your legal counsel in connection with this transaction, we
have examined the proceedings taken and are familiar with the proceedings taken
by you in connection with the sale and issuance of the Shares and the Warrant
Shares.

         It is our opinion that the Shares are legally and validly issued, fully
paid and non-assessable, and that the Warrant Shares, when issued pursuant to
the underlying warrants, will be validly issued, fully paid and nonassessable.

         We consent to the use of this opinion as an exhibit to the Registration
Statement and further consent to the use of our name wherever appearing in the
Registration Statement, including the prospectus constituting a part thereof,
and in any amendment thereto.


                                         Sincerely,

                                         /s/ HELLER EHRMAN WHITE & MCAULIFFE LLP