I've posted this question to the Gnome users list, but so far no luck, so I thought I'd mention this here.
A little while ago, I noticed that I was no longer able to log out from my GDM. I'm running the default GDM (2.16) that comes with CentOS, and this problem started up right about the same time that I updated to the 53.1.4 kernel (from the 8.1.15 version).
As I've posted here recent;y, I was unable to use yum to install the 53.1.6 kernel until I rebooted to the 53.1.4 default kernel (I run a modified kernel that has NTFS support built in as a module with read/write support.) However, I was not only unable to log out using the System->LogOut applet, I was also unable to shut down or reboot using the System->Shutdown applet.
This has also occurred since rebooting to the 53.1.6 stock kernel and my own 53.1.6 kernel with NTFS.
What happens is that I either click on the Log Out or Shutdown applet, and if I click on the relevant button (Log Out, Shutdown or Reboot), the applet freezes. I can't cancel it or change options (in the case of the shutdown applet), but if I click on the close window button (upper right hand corner), after a moment or two, the "not responding" window pops up and I can kill the applet. (Thsi also happens if I just let the applet time out - it freezes then, too.)
The only way I have been able to log out is to kill my gnome-session. To reboot, I can run "reboot" in a terminal window, or log out (by killing the gnome session) and then click on the "Reboot" link at the bottom of the login screen.
I confess that I have downloaded and installed a few third-party packages, but I got most of them via rpmforge, CentOS (Fedora) Extras and SourceForge.
The only thing that I find really suspicious in all of these is that I tried to install k9copy and it refused to install due to too many missing parts, but I did manage to install a number of KDE pieces - could they be interfering? Also, IIRC, the problem began before that, so I'm in a quandary here.
Part of the problem is that I rarely log out, so I'm not 100% sure of exactly when this started or what I last installed that might have triggered it. (BTW, how do I view that?)
Suggestions? Wisdom? Not too abrasive, please.... :-)
Thanks.
mhr