Please help! Very ambiguous call rejected message


I have an issue that is really driving me crazy. We have a SIP extension that, through the Extension Routes module from Schmooze, directs to an outbound route and directs to a SIP trunk that connects direct to our t.38 provider. Regarding my ambiguous message, this is the error message I am seeing, directly before the call goes to a fast busy sound.

NOTICE[1591]: chan_sip.c:23375 handle_request_invite: Call from ‘702’ (IP.ADD.RE.SS:5060) to extension ‘FAX15554443333’ rejected because extension not found in context ‘from-internal’.

I find I can call from a handset that won’t be using T.38 and it works fine… but when I use a fax machine to try to send out, somehow this message appears and the call is rejected. I have T.38 passthru turned on, ports 4000:4999 open in the firewall, and can confirm this happens every time I try to send a fax. If I make a voice call, it can connect… I am thinking something with the Audiocodes SIP ATA I am using is attempting T.38 and somehow Asterisk is intercepting this and giving me grief. Again, the same SIP registered RJ11 port works just fine when I plug a regular phone handset device in and call out… so it seems the problem is primarily when sending faxes…

Also, I’ve already now deleted and recreated the extension in Asterisk, as well as the outbound route and trunk.