You cannot forward a call between federated users in Communications Server 2007 R2

In a Microsoft Office Communications Server 2007 R2 environment, a user in the local enterprise calls a user in a federated partner enterprise. When the local user tries to forward the call to another user in the same federated partner enterprise, the call is not forwarded.

Note This issue occurs only in forwarded calls. Forwarded calls include call forwarding, boss/admin delegation, and team call scenarios. For direct calls, there is no problem transferring between federated users.

To resolve this issue, apply the following update: Note OCS 2007 R2 Access Proxy and Director must apply this update too.

Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.