[Freeswitch-users] Threaded IVR/Voicemail?

Hi, I got things working with openser by having freeswitch register as an sip user with openser. Freeswitch is an sip client that handles voicemail. The problem with this is multiple users simultaneously using voicemail is not possible. The Freeswitch user is busy with a single caller. If I attempt to just forward the call to freeswitch's ip address:5060 (without freeswitch registering to openser) freeswitch does not respond at all. I assume I need to do something in sofia.conf.xml, but I'm not sure. Any advice, even if I'm missing the obvious, would be very helpful. Thanks. MP