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

CUSIP NO. 00000X000                                           
          ---------

                                    EXHIBIT A
                                    ---------

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


         In accordance with Rule 13d-1(f) under the Securities Exchange Act of
1934, as amended, the persons named below each hereby agrees that the Schedule
13D filed herewith and any amendments thereto relating to the acquisition of
shares of the Common Stock of the Company is filed jointly on behalf of each
such person.

Dated: May 13, 1998

                                            X.X. XXXXXX & CO.

                                            By: /s/ Xxxxx X. Xxxxxx
                                            -----------------------
                                            Name:  Xxxxx X. Xxxxxx
                                            Title: President


                                            /s/ Xxxxx X. Xxxxxx
                                            -------------------
                                            Xxxxx X. Xxxxxx


                                            /s/ Xxxxx X. Xxxxxx
                                            -------------------
                                            Xxxxx X. Xxxxxx


                                            XXXXXX PARTNERS, L.P.

                                            By: XXXXXX CAPITAL CORPORATION
                                                 its general partner


                                            By: /s/ Xxxxx X. Xxxxxx
                                            -----------------------
                                            Name:  Xxxxx X. Xxxxxx
                                            Title: President


                                            XXXXXX CAPITAL CORPORATION

                                            By: /s/ Xxxxx X. Xxxxxx
                                            -----------------------
                                            Name:  Xxxxx X. Xxxxxx
                                            Title: President

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