My IP Communicator registered with CUCM 6.1 and subscribed on Extension Mobility service. I can see this service in IP Communicator but when check him I see "Host not found". On the IP Phone all services work. I try change CUCM hostname on IP address and service URL but it not help.
And another problem, VT advantage 2 work with one 7970 phone and don`t work with anotger 7970 phone. They have the same settings.