Comment 1 for bug 57774

I have seen this behavior as well. In many cases, I have retained keyboard control in whatever application had focus when the screensaver activated, but cannot navigate the desktop. Hotkeys do work, but I am usually unable to cleanly log out so I can restart X. I usually wind up having to hard reboot (X session freezes).

I am running Kubuntu 6.06 LTS on x86 architecture (Pentium D system), with 2GB of ram, and an Nvidia graphics card (I think it's a 4200, has 32 MB of RAM) running two monitors.