I think that James' comment 17 is right on spot with this problem and a few others files for gnome-power-manager. Judging by the description of the problems in those comments. Now it's up to ubuntu devs to pick up those patches and apply them :)
-- [karmic] display doesn't go to DPMS sleep https://bugs.launchpad.net/bugs/385633 You received this bug notification because you are a member of Ubuntu Desktop Bugs, which is subscribed to gnome-power-manager in ubuntu. -- desktop-bugs mailing list desktop-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/desktop-bugs