topher1086, did you manage to resolve this? I am having the same issue.

I had the same frustrating problem, but I finally managed to get my ATA187 faxing to work. The below is what I did:EQUIPMENT:CUCM 7.0.1 on MCS serversCisco 2901 Router configured as a H323 gatewayATA187 (2 units) ISDN PRI E1PREREQUISITES:Need to inst...