EXHIBIT 99.1 AGREEMENT REGARDING JOINT FILING UNDER UNDER RULE 13D-1(K) OF THE EXCHANGE ACT In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as amended, each of the undersigned agrees to the filing on behalf of each of a...

                                  EXHIBIT 99.1

                     AGREEMENT REGARDING JOINT FILING UNDER
                     UNDER RULE 13D-1(K) OF THE EXCHANGE ACT

In accordance with Rule 13d-1(k) under the Securities Exchange Act of 1934, as
amended, each of the undersigned agrees to the filing on behalf of each of a
Statement on Schedule 13G, and all amendments thereto, with respect to the
shares of Common Stock of Trestle Holdings, Inc.

Date: August 19, 2004


                                      /s/ Xxxx Xxxxxxxxx
                                      ----------------------------------
                                                Xxxx Xxxxxxxxx


                                      Xxxxxxxxx Qualified Partners, LP

                                      By: PRZ Holdings, LLC, its general partner

                                      By: /s/ Xxxx Xxxxxxxxx
                                          ------------------------------
                                          Name:  Xxxx Xxxxxxxxx
                                          Title: Managing Member


                                      Xxxxxxxxx Partners, L.P.

                                      By: PRZ Holdings, LLC, its general partner

                                      By: /s/ Xxxx Xxxxxxxxx
                                          ------------------------------
                                          Name:  Xxxx Xxxxxxxxx
                                          Title: Managing Member


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