A Communicator Web Access user who joins a conference as a federated user cannot share the computer desktop in Office Communications Server 2007 R2

Consider the following scenario:

• A Communicator Web Access (CWA) user in Microsoft Office Communications Server 2007 R2 joins a conference as a federated user.
• The CWA user logs on by using a computer that is external to the enterprise that is hosting the conference.

In this scneario, the CWA user may not be able to share the computer's desktop.

To resolve this issue, apply the following update:

• 967836  (http://support.microsoft.com/kb/967836/ ) Description of the update package for Office Communications Server 2007 R2, Communicator Web Access: April 2009

After you install this update, CWA uses the correct information to route desktop sharing information to the Office Communications Server server.

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