We have a configuration that includes legacy fax machines on VG224's configured for MGCP with T38 inhibited and the PSTN voice gateway is enabled to support T38 for CCM 4.2 integration of a Xmedius fax server. The process theory (supported by other posts I might add) is upon voice to fax negotiation the VG224's with T38 inhibited will invoke fax pass-thru with the PSTN VG. However, we find only outbound works correctly. Inbound appears to have negotiated correctly but drops the call every time.

IOS is 12.4.13d and CUCM is 4.2(3)sr3.

Any real-world experience out there with this type of configuration?

I will attach vg config files for refernce in a moment.

Jon