Exhibit 99.1

      CERTIFICATION OF CHIEF EXECUTIVE OFFICER AND CHIEF FINANCIAL OFFICER
                                  PURSUANT TO
                            18 U.S.C. SECTION 1350,
                             AS ADOPTED PURSUANT TO
                  SECTION 906 OF THE SARBANES-OXLEY ACT OF 2002

        I, John H. Kunze, certify, pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the
Quarterly Report of Plumtree Software, Inc. on Form 10-Q for the quarterly
period ended June 30, 2002 fully complies with the requirements of Section 13(a)
or 15(d) of the Securities Exchange Act of 1934 and that information contained
in such Form 10-Q fairly presents in all material respects the financial
condition and results of operations of Plumtree Software, Inc.

                                 By:    /s/ John H. Kunze
                                        ------------------
                                 Name:  John H. Kunze
                                 Title: Chief Executive Officer

        I, Eric Borrmann, certify, pursuant to 18 U.S.C. Section 1350, as
adopted pursuant to Section 906 of the Sarbanes-Oxley Act of 2002, that the
Quarterly Report of Plumtree Software, Inc, on Form 10-Q for the quarterly
period ended June 30, 2002 fully complies with the requirements of Section 13(a)
or 15(d) of the Securities Exchange Act of 1934 and that information contained
in such 10-Q fairly presents in all material respects the financial condition
and results of operations of Plumtree Software, Inc.

                                 By:    /s/ Eric Borrmann
                                        ----------------------
                                 Name:  Eric Borrmann
                                 Title: Chief Financial Officer