Windows 7, Bitlocker and failed shutdowns

Scenario
Windows 7 computer has been shutting down with no problesm
You subsequently enable BitLocker and the computer doesn't turn off at shutdown.

Symptoms:-

Windows Shutdown normally

Black screen

Power Light on

No issues in the Event Logs

Windows doesn't report any shutdown problems on next startup

Fix:-
Microsoft have released a hotfix, which looks like it was released in November 2009 and is not available via Windows or Microsoft Update.

You can find it here:- http://support.microsoft.com/kb/975496

You have to submit your details and they send you an email with a link almost immediatly.