I have been trying to get T.38 fax relay to work with calls going from a 1760 router PRI PSTN connection to callmanager and then to a GFI fax maker fax server. I can fax outbound from GFI faxmaker to an outside analog fax machine and it works fine, however if I try an inbound fax call to the fax server coming from the PSTN the fax server sees the call but it is immediately disconnected, I'm assuming because of a lack of T.38 recognition. Even a debug fax relay t30 all only gives me output on outbound fax calls and nothing on inbound ones. Does anyone have any ideas? The connection from the router to the callmanagers is MGCP and the connection from callmangager to the fax server is SIP. We are running version 6.0.1.2000-4 of callmanager and have 12.4(17) code on the 1760 router. A short set of my mgcp configuration is below. Any advice would be appreciated. Cisco TAC is telling me I might need to use a hardware MTP, but I'm not sure about that and they have so far been unable to help me get that setup right either.
ccm-manager redundant-host 172.16.1.15
ccm-manager mgcp
ccm-manager music-on-hold
ccm-manager config server 172.16.1.20 172.16.1.15
ccm-manager config
!
mgcp
mgcp call-agent 172.16.1.20 2427 service-type mgcp version 0.1
mgcp dtmf-relay voip codec all mode out-of-band
mgcp rtp unreachable timeout 1000 action notify
mgcp modem passthrough voip mode nse
mgcp package-capability rtp-package
mgcp package-capability sst-package
mgcp default-package fxr-package
no mgcp package-capability res-package
no mgcp timer receive-rtcp
mgcp sdp simple
mgcp rtp payload-type g726r16 static
!
mgcp profile default
