Microsoft recently pushed updates out to the world which install the Windows Management Framework 3.0 on 'older' operating systems like Windows Server 2008 and 2008 R2.
The updates are available through http://support.microsoft.com/kb/2506143 and http://support.microsoft.com/kb/2506146
However, some sources reported having issues with Exchange 2007 and Exchange 2010 after installing these updates. Although these problems haven't been officially confirmed (yet), I would like to ask you to be prudent and NOT install them until more is known. Given that these updates are available through Windows Update, please make sure they are not installed automatically.
I have planned to do some testing over the weekend, so I hope to be able to tell you more by Monday.
This again proves that it's very important to TEST updates before putting them into production. It's a best practice anyway. Even if you don't have a test-environment at hand, it might be worth running a single Exchange-VM somewhere to do some rudimentary testing. Perhaps you won't be able to cover every scenario, but it will at least help you filtering out problems like these.
Michael Van Horenbeeck