JOINT FILING AGREEMENT

                                                                       EXHIBIT A
                                                                  Conformed Copy


                             JOINT FILING AGREEMENT

We, NRL Acquisition Corp. and Xxxxxx Resources Limited, the signatories of the
statement on Schedule 13D to which this Joint Filing Agreement is attached,
hereby agree that such statement is filed jointly on behalf of NRL Acquisition
Corp. and Xxxxxx Resources Limited. Any subsequent amendments thereto filed by
any of us will be filed jointly on behalf of NRL Acquisition Corp. and Xxxxxx
Resources Limited.


Dated:   May 21, 2004


                                                NRL ACQUISITION CORP.

                                                By  \s\ R. Xxxxxxxxx Xxxxxx
                                                    -----------------------
                                                    R. Xxxxxxxxx Xxxxxx
                                                    President

                                                XXXXXX RESOURCES LIMITED

                                                By  \s\ R. Xxxxxxxxx Xxxxxx
                                                    -----------------------
                                                    R. Xxxxxxxxx Xxxxxx
                                                    Chief Financial Officer