Article ID: 949894 - View products that this article applies to.
When you use a time zone that includes a negative partial hour on a client computer, the presence functions are disabled in Microsoft Office Communicator 2007. For example, this problem occurs when the time zone is set to (GMT-04:30) Caracas.
This problem occurs because the UCCP stack incorrectly tries to use negative minutes together with the negative hour value.
To resolve this problem, install the Communicator 2007 update package that is dated March 28, 2008. For more information, click the following article number to view the article in the Microsoft Knowledge Base:
(http://support.microsoft.com/kb/946164/ )Description of the update for Communicator 2007: April 2, 2008
Microsoft has confirmed that this is a bug in the Microsoft products that are listed in the "Applies to" section.