FC3 upgrade - can't logout!

[Simon Andrews <simon.andrews@xxxxxxxxxxx>]

I've just upgraded our development machine from FC2 -> FC3.  Whilst 
everything seems to be up and running I've hit a problem that I can't 
logout from a gnome session.

We've had similar problems on this machine before (PowerEdge 2500), but 
before we used to get the logout box and then after selecting logout the 
screen would sometimes freeze for 30secs or so before returning you to 
the login prompt.  Now I don't even get the logout box appear and the 
session carries on as it nothing had happened.  The only way to get out 
is to kill X.

I've grepped the running processes for "logout" but get nothing back. 
Can anyone suggest how I can start to debug this?

Cheers

Simon.