JOINT FILING AGREEMENT ----------------------

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                                    EXHIBIT I

                             JOINT FILING AGREEMENT
                             ----------------------

Each of the undersigned hereby agrees that the Schedule 13G filed herewith is
filed jointly on behalf of each of them pursuant to Rule 13d-1(k)(1) under the
Securities Exchange Act of 1934, as amended.


                                    SIGNATURE

After reasonable inquiry and to the best of the undersigned's knowledge and
belief, the undersigned certifies that the information set forth in this
statement is true, complete, and correct.


DATE: February 8, 2000



                                             BRENTWOOD ASSOCIATES VI, L.P.,
                                             a Delaware limited partnership

                                             By: Brentwood VI Ventures L.P.,
                                                 a Delaware limited partnership
                                                 Its:  General Partner


                                                 By: /s/ G. Xxxxxxxx Xxxxx
                                                     ---------------------------
                                                     G. Xxxxxxxx Xxxxx
                                                     General Partner


                                             BRENTWOOD VI VENTURES, L.P.,
                                             a Delaware limited partnership

                                             By: /s/ G. Xxxxxxxx Xxxxx
                                                 -------------------------------
                                                 G. Xxxxxxxx Xxxxx
                                                 General Partner


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