Exhibit B JOINT FILING AGREEMENT This Agreement is filed as an exhibit to Schedule 13G/A being filed by Potomac Capital Management LLC, Potomac Capital Management Inc., and Paul J. Solit in compliance with Rule 13d-1(k) of the Securities and Exchange...

Exhibit B



                             JOINT FILING AGREEMENT

                     This Agreement is filed as an exhibit to Schedule 13G/A
         being filed by Potomac Capital Management LLC, Potomac Capital
         Management Inc., and Xxxx X. Xxxxx in compliance with Rule 13d-1(k) of
         the Securities and Exchange Commission, which requires an agreement in
         writing indicating that the Schedule 13G/A to which this Agreement is
         attached is filed on behalf of the below-named entities, that they are
         each responsible for the timely filing of the Schedule 13G and any
         amendments thereto and for the completeness and accuracy of the
         information concerning such persons contained therein.


         Dated: January 2, 2008




                                       POTOMAC CAPITAL MANAGEMENT LLC

                                       By:    /s/      Xxxx X. Xxxxx
                                             -----------------------
                                              Xxxx X. Xxxxx, Managing Member

                                       POTOMAC CAPITAL MANAGEMENT INC.

                                       By:    /s/     Xxxx X. Xxxxx
                                              ---------------------
                                               Xxxx X. Xxxxx, President


                                       XXXX X. XXXXX

                                       By:     /s/ Xxxx X. Xxxxx
                                              ---------------------
                                               Xxxx X. Xxxxx