I've configured powerdevil to look my screen after 15 min inactivity, however powerdevil simple ignores this setting.
I think, this problem first appeared after the update 4.7.2 -> 4.7.3 (openSuse 11.4 -> openSuse 12.1)

I already tried creating a new user but this problem still exists.

Not sure if this is a bug, or if I'm the only one with this problem.