Article ID: 981439 - View products that this article applies to.
When group chat users change chat rooms by using Microsoft Office Communications Server 2007 R2 Group Chat clients, performance is degraded on the group chat server.
To fix this problem, apply the following update:
(http://support.microsoft.com/kb/980043/ )Description of the update for Office Communications Server 2007 R2, Group Chat Client: March 2010
Microsoft has confirmed that this is a problem in the Microsoft products that are listed in the "Applies to" section.