Shared Fax not working properly an XP workstation.

I have Microsoft Fax Service installed on a SBS 2003 server. It works fine. I
have installed it on another XP workstation in the office and it works fine
there, too.

But I've installed it on another workstation and I'm unable to fax from that
XP workstation. I can see all of the faxes that have been sent from the
server, but my faxes just stay in the queue. I'm installing it as a shared
printer from the server.

Any thoughts as to what might be wrong?

Thanks!