We just have done MS OCS R2 and Cisco CUCM6.1 integration and most of features work as expected. As there is no DID for each user, external incoming calls are transferred to internal extension using AA in Unity 5.01 then ring on both of Cisco phone and Office Communicator (CUCM Unified Mobility feature).
Now the problem is that the caller ID displays on Office Communicator is the number of Unity voicemail ports, but not the orignal calling number.
When I check SIP messages on MS mediation server, it shows the number of Unity voicemail ports is sent to OCS.
The caller name and caller ID on Cisco phone are correct.
Call main number --> Cisco 2851, PRI --> CUCM6.1 --> Unity Call Handler --> CUCM6.1 --> ring Cisco phone
SIP trunk --> OCS Mediation --> OCS
Is there anyway to configure CUCM to send orignal calling number over SIP trunk to OCS?
try to change "Display Original Calling Number on Transfer from Cisco Unity" in CCM service parameter configuration to true,
it is set to false by default.