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                                                                   Exhibit 10.20

THIS WARRANT AND THE SHARES ISSUABLE HEREUNDER HAVE NOT BEEN REGISTERED UNDER
THE SECURITIES ACT OF 1933, AS AMENDED, AND MAY NOT BE SOLD, PLEDGED OR
OTHERWISE TRANSFERRED WITHOUT AN EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT
OR PURSUANT TO RULE 144 OR AN OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE
CORPORATION AND ITS COUNSEL THAT SUCH REGISTRATION IS NOT REQUIRED.

                           WARRANT TO PURCHASE STOCK

Corporation:             2Bridge Software, A California Corporation
Number of Shares:        85,221 (subject to Section 1.7)
Class of Stock:          Series B Preferred (subject to Section 1.7)
Initial Exercise Price:  $1.4081 per share (subject to Section 1.7)
Issue Date:              May 1, 1999
Expiration Date:         May 1, 2006 (Subject to Article 4.1)

     THIS WARRANT CERTIFIES THAT, in consideration of the payment of $1.00 and
for other good and valuable consideration, IMPERIAL BANCORP or its registered
assignee (together with its successors and assigns "Holder") is entitled to
purchase the number of fully paid and nonassessable shares of the class of
securities (the "Shares") of the corporation (together with its successors and
assigns, the "Company") at the initial exercise price per Share (the "Warrant
Price") all as set forth above and as adjusted pursuant to Article 2 of this
Warrant, subject to the provisions and upon the terms and conditions set forth
of this Warrant.

ARTICLE 1. EXERCISE
           --------

     1.1  Method of Exercise. Holder may exercise this Warrant by delivering
          ------------------
this Warrant and a duly executed Notice of Exercise in substantially the form
attached as Appendix 1 to the principal office of the Company. Unless Holder is
exercising the conversion right set forth in Section 1.2, Holder shall also
deliver to the Company a check for the aggregate Warrant Price for the Shares
being purchased.

     1.2  Conversion Right. In lieu of exercising this Warrant as specified in
          ----------------
Section 1.1, Holder may from time to time convert this Warrant, in whole or in
part, into a number of Shares determined by dividing (a) the aggregate fair
market value of the Shares or other securities otherwise issuable upon exercise
of this Warrant minus the aggregate Warrant Price of such Shares by (b) the fair
market value of one Share. The fair market value of the Shares shall be
determined pursuant to Section 1.5.
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     1.3  Fair Market Value. If the Shares are traded regularly in a public
          -----------------
market, the fair market value of the Shares shall be the closing price of the
Shares (or the closing price of the Company's stock into which the Shares are
convertible) reported for the business day immediately before Holder delivers
its Notice of Exercise to the Company. If the Shares are not regularly traded in
a public market, the Board of Directors of the Company shall determine the fair
market value in its reasonable good faith judgment. The foregoing
notwithstanding, if Holder advises the Board of Directors in writing that Holder
disagrees with such determination, then the Company and Holder shall promptly
agree upon a reputable investment banking firm to undertake such valuation, if
the valuation of such investment banking firm is greater than five (5%) percent
or more than that determined by the Board of Directors, then all fees and
expenses of such investment banking firm shall be paid by the Company. In all
other circumstances, such fees and expenses shall be paid by Holder.

     1.4  Delivery of Certificate and New Warrant. Promptly after Holder
          ---------------------------------------
exercises or converts this Warrant, the Company shall deliver to Holder
certificates for the Shares acquired and, if this Warrant has not been fully
exercised or converted and has not expired, a new Warrant representing the
Shares not so acquired.

     1.5  Replacement of Warrants. On 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, on delivery of an
indemnity agreement reasonably satisfactory in form and amount to the Company
or, in the case of mutilation, or surrender and cancellation of this Warrant,
the Company at its expense shall execute and deliver, in lieu of this Warrant, a
new warrant of like tenor.

     1.6  Repurchase on Sale, Merger, or Consolidation of the Company.
          -----------------------------------------------------------

          1.6.1.  "Acquisition". For the purpose of this Warrant, "Acquisition"
                   -----------
means any sale, license, or other disposition of all or substantially all of the
assets (including intellectual property) of the Company, or any reorganization,
consolidation, or merger of the Company where the holders of the Company's
securities before the transaction beneficially own less than 50% of the
outstanding voting securities of the surviving entity after the transaction.

          1.6.2.  Assumption of Warrant. If upon the closing of any Acquisition
                  ---------------------
the successor entity assumes the obligations of this Warrant, then this Warrant
shall be exercisable for the same securities, cash, and property as would be
payable for the Shares issuable upon exercise of the Unexercised portion of this
Warrant as if such Shares were outstanding on the record date for the
Acquisition and subsequent closing. The Warrant Price shall be adjusted
accordingly. The Company shall use reasonable efforts to cause the surviving
corporation to assume the obligations of this Warrant.

          1.6.3.  Nonassumption. If upon the closing of any Acquisition the
                  -------------
successor entity does not assume the obligations of this Warrant and Holder has
not otherwise exercised this Warrant in full, then the unexercised portion of
this Warrant shall be deemed to have been automatically converted pursuant to
Section 1.2 and thereafter Holder shall participate in the Acquisition on the
same terms as other holders of the same class of securities of the Company.

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     1.7  Adjustment in Underlying Preferred Stock Price and Exercise Price. If
          -----------------------------------------------------------------
on or before July 31, 1999, the Company sells and issues to any investors,
preferred stock with aggregate gross proceeds to the Company of at least
$6,000,000 (six million dollars), this Warrant shall concurrent with the
issuance of such shares of preferred stock automatically be adjusted to instead
be exercisable for shares of the same series and class and bearing the same
rights, preferences, and privileges, of such shares of stock, with the Warrant
Price hereunder adjusted to equal the per share purchase price of such stock,
and the number of such shares subject to this Warrant adjusted to equal (i) one
hundred twenty thousand dollars ($120,000)*, divided by (ii) such modified per
share Warrant Price.


ARTICLE 2. ADJUSTMENTS TO THE SHARES.
           -------------------------

     2.1  Stock Dividends, Splits, Etc. If the Company declares or pays a
          ----------------------------
dividend on its common stock payable in common stock, or other securities,
subdivides the outstanding common stock into a greater amount of common stock,
then upon exercise of this Warrant, for each Share acquired, Holder shall
receive, without cost to Holder, the total number and kind of securities to
which Holder would have been entitled had Holder owned the Shares of record as
of the date the dividend or subdivision occurred.

     2.2  Reclassification, Exchange or Substitution. Upon any reclassification,
          ------------------------------------------
exchange, substitution, or other event that results in a change of the number
and/or class: of the securities issuable upon exercise or conversion of this
Warrant, Holder shall be entitled to receive, upon exercise or conversion of
this Warrant, the number and kind of securities and property that Holder would
have received for the Shares if this Warrant had been exercised immediately
before such reclassification, exchange, substitution, or other event. Such an
event shall include any automatic conversion of the outstanding or issuable
securities of the Company of the same class or series as the Shares to common
stock pursuant to the terms of the Company's Articles of Incorporation upon the
closing of a registered public offering of the Company's common stock. The
Company or its successor shall promptly issue to Holder a new Warrant for such
new securities or other property. The new Warrant shall provide for adjustments
which shall be as nearly equivalent as may be practicable to the adjustments
provided for in this Article 2 including, without limitation, adjustments to the
Warrant Price and to the number of securities or property issuable upon exercise
of the new Warrant. The provisions of this Section 2.2 shall similarly apply to
successive reclassifications, exchanges, substitutions, or other events.

     2.3  Adjustments for Combinations, Etc. If the outstanding shares are
          ---------------------------------
combined or consolidated, by reclassification or otherwise, into a lesser number
of shares, the Warrant Price shall be proportionately increased.

     2.4  Adjustments for Diluting Issuances. The number of shares of common
          ----------------------------------
stock issuable upon conversion of the Shares issuable upon exercise of this
Warrant shall be subject to adjustment, from time to time, in the manner set
forth on Exhibit A, if attached, in the event of Diluting Issuances (as defined
on Exhibit A).

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     2.5  No Impairment. The Company shall not, by amendment of its Articles of
          -------------
Incorporation or through a reorganization, transfer of assets, consolidation,
merger, dissolution, issue, or sale of securities or any other voluntary action,
avoid or seek to avoid the observance or performance of any of the terms to be
observed or performed under this Warrant by the Company, but shall at all times
in good faith assist in carrying out all the provisions of this Article 2 and in
taking all such action as may be necessary or appropriate to protect Holder's
rights under this Article against impairment. If the Company takes any action
affecting the Shares or its common stock other than as described above that
adversely affects Holder's rights under this Warrant, the Warrant Price shall be
adjusted downward and the number of Shares issuable upon exercise of this
Warrant shall be adjusted upward in such a manner that the aggregate Warrant
Price of this Warrant is unchanged.

     2.6  Certificate as to Adjustments. Upon each adjustment of the Warrant
          -----------------------------
Price, the Company at its expense shall promptly compute such adjustment, and
furnish Holder with a certificate of its Chief Financial Officer setting forth
such adjustment and the facts upon which such adjustment is based. The Company
shall, upon written request, furnish Holder a certificate setting forth the
Warrant Price in effect upon the date thereof and the series of adjustments
leading to such Warrant Price.

ARTICLE 3. REPRESENTATIONS AND COVENANTS OF THE COMPANY.
           --------------------------------------------

     3.1  Representations and Warranties. The Company hereby represents and
          ------------------------------
warrants to the Holder as follows:

          (a) The initial Warrant Price referenced on the first page of this
Warrant is not greater than the fair market value of the Shares as of the date
of this Warrant.

          (b) All Shares which may be issued upon the exercise of the purchase
right represented by this Warrant, and all securities, if any, issuable upon
conversion of the Shares, shall, upon issuance, be duly authorized, validly
issued, fully paid and nonassessable, and free of any liens and encumbrances
except for restrictions on transfer provided for herein or under applicable
federal and state securities laws.

     3.2  Notice of Certain Events. If the Company proposes at any time (a) to
          ------------------------
declare any dividend or distribution upon its common stock, whether in cash,
property, stock, or other securities and whether or not a regular cash dividend;
(b) to effect any reclassification or recapitalization of common stock; (c) to
merge or consolidate with or into any other corporation, or sell, lease,
license, or convey all or substantially all of its assets, or to liquidate,
dissolve or wind up; or (d) to offer holders of registration rights the
opportunity to participate in an underwritten public offering of the company's
securities for cash, then, in connection with each such event, the Company shall
give Holder (1) at least 20 days prior written notice of the date on which a
record will be taken for such dividend, distribution, or subscription rights
(and specifying the date on which the holders of common stock will be entitled
thereto) or for determining rights to vote, if any, in respect of the matters
referred to in (b) and (c) above; (2) in the case of the matters referred to in
(b) and (c) above at least 20 days prior written notice of the date when the
same will take place (and specifying the date on which the holders of common
stock will be entitled to exchange their common stock for securities or other
property deliverable upon the occurrence of such

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event); and (3) in the case of the matter referred to in (d) above, the same
notice as is given to the holders of such registration rights.

     3.3  Information Rights. So long as the Holder holds this Warrant and/or
          ------------------
any of the Shares, the Company shall deliver to the Holder (a) promptly after
mailing, copies of all communiques to the shareholders of the Company, (b)
within one hundred fifty (150) days after the end of each fiscal year of the
Company, the annual audited financial statements of the Company certified by
independent public accountants of. recognized standing and (c) within forty-five
(45) days after the end of each of the first three quarters of each fiscal year,
the Company's quarterly, unaudited financial statements.

     3.4  Registration Under Securities Act of 1933, as amended. The Company
          -----------------------------------------------------
agrees that the Shares shall be subject to the registration rights set forth on
Exhibit B.

ARTICLE 4. MISCELLANEOUS.
           -------------

     4.1  Term: Notice of Expiration. This Warrant is exercisable, in whole or
          --------------------------
in part, at any time and from time to time on or before the Expiration Date set
forth above.

     4.2  Legends. This Warrant and the Shares (and the securities issuable,
          -------
directly or indirectly, upon conversion of the Shares, if any) shall be
imprinted with a legend in substantially the following form:

     THIS SECURITY HAS NOT BEEN REGISTERED UNDER THE SECURITIES ACT OF 1933, AS
     AMENDED, AND MAY NOT BE SOLD, PLEDGED OR OTHERWISE TRANSFERRED WITHOUT AN
     EFFECTIVE REGISTRATION THEREOF UNDER SUCH ACT OR PURSUANT TO RULE 144 OR AN
     OPINION OF COUNSEL REASONABLY SATISFACTORY TO THE CORPORATION AND ITS
     COUNSEL THAT SUCH REGISTRATION IS NOT REQUIRED.

     4.3  Compliance with Securities Laws on Transfer. This Warrant and the
          -------------------------------------------
Shares issuable upon exercise of this Warrant (and the securities issuable,
directly or indirectly, upon conversion of the Shares, if any) may not be
transferred or assigned in whole or in part without compliance with applicable
federal and state securities laws by the transferor and the transferee
(including, without limitation, the delivery of investment representation
letters and legal opinions reasonably satisfactory to the Company). The Company
shall not require Holder to provide an opinion of counsel if the transfer is to
an affiliate of Holder or if there is no material question as to the
availability of current information as referenced in Rule 144(c), Holder
represents that it has complied with Rule 144(d) and (e) in reasonable detail,
the selling broker represents that it has complied with Rule 144(f), and the
Company is provided with a copy of Holder's notice of proposed sale.

     4.4  Transfer Procedure. Subject to the provisions of Section 4.3, Holder
          ------------------
may transfer all or part of this Warrant or the Shares issuable upon exercise of
this Warrant (or the securities issuable, directly or indirectly, upon
conversion of the Shares, if any) by giving the Company notice of the portion of
the Warrant being transferred setting forth the name, address and taxpayer
identification number of the transferee and surrendering this Warrant to the
Company for reissuance to the transferee(s) (and Holder, if

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<PAGE>

applicable). Unless the Company is filing financial information with the SEC
pursuant to the Securities Exchange Act of 1934, the Company shall have the
right to refuse to transfer any portion of this Warrant to any person who
directly competes with the Company.

     4.5  Notices. All notices and other communications from the Company to the
          -------
Holder, or vice versa, shall be deemed delivered and effective when given
personally or mailed by first-class registered or certified mail, postage
prepaid, or sent by recognized overnight courier at such address as may have
been furnished to the Company or the Holder, as the case may be, in writing by
the Company or such Holder from time to time.

     4.6  Waiver. This Warrant and any term hereof may be changed, waived,
          ------
discharged or terminated only by an instrument in writing signed by the party
against which enforcement of such change, waiver, discharge or termination is
sought.

     4.7  Attorneys' Fees. In the event of any dispute between the parties
          ---------------
concerning the terms and provisions of this Warrant, the party prevailing in
such dispute shall be entitled to collect from the other party all costs
incurred in such dispute, including reasonable attorneys' fees.

     4.8  Governing Law. This Warrant shall be governed by and construed in
          -------------
accordance with the laws of the State of California, without giving effect to
its principles regarding conflicts of law.

2Bridge Software

By: /s/ Ronald Parks                    By:________________________________
   -------------------------------

Name:   Ronald Parks                    Name:______________________________
     -----------------------------

Title:  CFO                             Title:_____________________________
      ----------------------------

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<PAGE>

                                  APPENDIX 1

                              NOTICE OF EXERCISE
                              ------------------

     1.  The undersigned hereby elects to purchase ____________ shares of the
Common Stock of 2Bridge Software, A California corporation, pursuant to the
terms of the attached Warrant, and tenders herewith payment of the purchase
price of such shares in full.

     1.  The undersigned hereby elects to convert the attached Warrant into
Shares in the manner specified in the Warrant. This conversion is exercised with
respect to ___________ of the Shares covered by the Warrant.

     [Strike paragraph that does not apply.]

     2.  Please issue a certificate or certificates representing said shares in
the name of the undersigned or in such other name as is specified below:

               Chief Financial Officer
               Controllers Department
               Imperial Bancorp
               P.O. Box 92991
               Los Angeles, CA 90009
               Or Registered Assignee

     3.  The undersigned represents it is acquiring the shares solely for its
own account and not as a nominee for any other party and not with a view toward
the resale or distribution thereof except in compliance with applicable
securities laws.

IMPERIAL BANCORP or Registered Assignee

_________________________________________
(Signature)

_____________________
(Date)

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<PAGE>

                                   EXHIBIT A
                                   ---------

                           Anti-Dilution Provisions

     In the event of the issuance (a "Diluting Issuance") by the Company, after
the Issue Date of the Warrant, of securities at a price per share less than the
Warrant Price, then the number of shares of common stock issuable upon
conversion of the Shares shall be adjusted in accordance with those provisions
(the "Provisions") of the Company's Articles (Certificate) of Incorporation
which apply to Diluting Issuances.

     The Company agrees that the Provisions, as in effect on the Issue Date,
Shall be deemed to remain in full force and effect during the term of the
Warrant notwithstanding any subsequent amendment, waiver or termination thereof
by the Company's shareholders.

     Under no circumstances shall the aggregate Warrant Price payable by the
Holder upon exercise of the Warrant increase as a result of any adjustment
arising from a Diluting Issuance.

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<PAGE>

                                   EXHIBIT B
                                   ---------

                              Registration Rights
                              -------------------

     The Shares shall be deemed "registrable securities" or otherwise entitled
to "piggy back" registration rights in accordance with the terms of the
following agreement (the "Agreement") between the Company and its investor(s):

Amended and Restated Investors' Rights Agreement dated May 18, 1998 among the
Company and the shareholders party thereto (holders of Series A and Series B
Preferred Stock)

     The Company agrees that no amendments will be made to the Agreement which
would have an adverse impact on Holder's registration thereunder without the
consent of Holder. By acceptance of the Warrant to which this Exhibit B is
attached, Holder shall not be deemed to be a party to the Agreement, but solely
entitled to the registration rights created thereby.

     If no Agreement exists, then the Company and the Holder shall enter into
Holder's standard form of Registration Rights Agreement as in effect on the
Issue Date of the Warrant.

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