Reporting services unavailable after windows 2003 SP2 installed

I have installed windows server 2003 on one of our test boxes (prior to live) and found that reporting services is now unavailable.

When I browse to the report server I get

Service Unavailable

The event log reports several times

"A process serving application pool 'reportserver' terminated unexpectedly. The process id was '3500'. The process exit code was '0xffffffff'.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.

before the worker process is disabled:

"Application pool 'reportserver' is being automatically disabled due to a series of failures in the process(es) serving that application pool.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp."

Has anyone seen similar behavior?

Stuart

"
A second reboot seems to have fixed this and (mysteriously enough) fixed terminal services too!