There is an issue with Office Server SP2 where a product expiration date is improperly activated. This means SharePoint will expire as though it was a trial 180 days after SP2 was deployed. This will not affect the normal function of SharePoint up until the expiration date passes. See Brian Smith's blog for more details and a workaround.

Addtionally, see the <a href="http://blogs.msdn.com/sharepoint/archive/2009/05/21/attention-important-in