<DOCUMENT>
<TYPE>EX-99
<SEQUENCE>3
<FILENAME>s11-7108_ex99b.txt
<DESCRIPTION>EXHIBIT 99B
<TEXT>
Exhibit B

                             JOINT FILING AGREEMENT

     The undersigned hereby agree that the Statement on Schedule 13G/A, and any
further amendments thereto executed by each and any of us shall be filed on
behalf of each of us pursuant to and in accordance with the provisions of Rule
13d-1(k)(1) under the Securities Exchange Act of 1934, as amended.

     This Agreement may be executed in separate counterparts, each of which
shall be deemed an original, but all of which shall constitute one and the same
instrument.

Dated: February 15, 2007

                                            POTOMAC CAPITAL MANAGEMENT LLC

                                            By:   /s/ Paul J. Solit
                                                  ------------------------------
                                                  Paul J. Solit, Managing Member

                                            POTOMAC CAPITAL MANAGEMENT INC.

                                            By:   /s/ Paul J. Solit
                                                  ------------------------------
                                                  Paul J. Solit, President

                                            PAUL J. SOLIT

                                            By:   /s/ Paul J. Solit
                                                  ------------------------------
                                                  Paul J. Solit

</TEXT>
</DOCUMENT>
