Compiz inhibits screensaver or causes crash on resume

[DJ Dallas]

Binary package hint: compiz

Enabling compiz prevents the screensaver from coming on and any further powersaving features to work. Turning screensaver off (with compiz enabled) allows display blanking and standby to function normally.

Deselecting 'Undirect Fullscreen Windows' in CompizConfig general settings will allow screensaver, display blanking and standby. However, when resuming from standby the computer locks up and fails to start. Also, switching users occasionally causes white screens in place of password dialogue (when lock screen option is required by one or both users).

Disabling compiz allows everything to work fine (screensaver, display blanking, standby, resume, and user switching with or without password after locked screen).

Note that I am using Nvidia-glx-177 restricted drivers as suspend and hibernate (and obviously compiz) will not work without them.

ProblemType: Bug
Architecture: i386
DistroRelease: Ubuntu 8.10
NonfreeKernelModules: nvidia
Package: compiz 1:0.7.7+git20080807-0ubuntu12
PackageArchitecture: all
ProcEnviron:
 PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin:/usr/games
 LANG=en_ZA.UTF-8
 SHELL=/bin/bash
SourcePackage: compiz
Uname: Linux 2.6.27-4-generic i686

[DJ Dallas (djdallas)]

This bug is probably a duplicate of Bug #159263, so I'll mark it as such.

Duplicated the crash twice before filing, crashed it again and then just left it for a while during lunch. When returning the startup framebuffer output said something about a call trace. This time round, after the resume, the system didn't crash, but instead resumed with a black screen with mouse cursor. Typed password and displayed a window which was open before standby, but otherwise was completely black. Alt-tab brought back my normal desktop.

By the way, the machine was put into standby when two user sessions were logged on.

Attaching dmesg and lspci