Following the first reboot for a couple of weeks, this problem has appeared for me. It's a Lenovo z61m laptop. I tried captwiggum's tactic to kill and restart gnome-power-manager, and the resulting log is attached.
The restart hung for quite a long time after line 179:
Code:
TI:07:41:01 TH:0x85166d8 FI:gpm-engine.c FN:gpm_engine_get_warning_time,158
- time zero, falling back to percentage for battery
Using pm-suspend from the command line works (but doesn't lock the screen).
I'm also running Compiz with the desktop cube.
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