SBS 2008 FAX PROBLEM

Hi All

I have a little bit of a problem which i cant seem to get my head around. I have a Windows SBS 2008 server configured to be a fax server.

I can send faxes perfectly and recieve from the server perfectly but when i go to a xp machine on my network i can connect fine but when i send i fax it disappears and doesnt get to the server.

Has anyone got any ideas 🙂

Thanks

Scott