I noticed that running the gnome-display-properties application also triggers this; I was able to consistently trigger this bug by:
1) first having my external monitor unplugged
2) plugging it in; at this point, nothing happens.
3) start gnome-display-properties -> X.org goes insane and the display properties app stays unresponsive.
(it appears to work if gnome-power-manager is not running, but clicking "detect monitors" seems to trigger the bug regardless.)
I noticed that running the gnome-display- properties application also triggers this; I was able to consistently trigger this bug by:
1) first having my external monitor unplugged properties -> X.org goes insane and the display properties app stays unresponsive.
2) plugging it in; at this point, nothing happens.
3) start gnome-display-
(it appears to work if gnome-power-manager is not running, but clicking "detect monitors" seems to trigger the bug regardless.)