We had GMS working with a few test users and then decided to rollout.
System appears to have stopped working correctly with event log entry
at 01.00 as follows

Event Type: Warning
Event Source: W3SVC
Event Category: None
Event ID: 1021
Date: 10/02/2007
Time: 01:00:26
User: N/A
Computer: SYNC
Description:
The identity of application pool, 'IntellisyncMobileSuiteAdminAppPool'
is invalid. If it remains invalid when the first request for the
application pool is processed, the application pool will be disabled.
And then...

Event Type: Error
Event Source: W3SVC
Event Category: None
Event ID: 1059
Date: 10/02/2007
Time: 01:00:41
User: N/A
Computer: SYNC
Description:
A failure was encountered while launching the process serving
application pool 'IntellisyncMobileSuiteAppPool'. The application pool
has been disabled.

Any ideas?

Andrew