[gpm] screen brightness on plug/unplug

[don-gpm isis cs3-inc com (Don Cohen)]

I've noticed that when I reconnect power to my laptop I often have
a dim screen.  If I click on the battery icon and select preferences
I see a "Power Management Preferences" window with a "set display
brightness" slider in the "On AC Power" tab.
This is (correctly) set to 80%.  If I then move it, say, to 79% the
screen gets brighter (I suppose to 79%).  I've been doing this and 
then moving it back to 80% and closing the window whenever I notice
the problem, which is most of the time when I reconnect power.
I assume I should not have to do this.  I'd appreciate advice on how
to make that manual step unnecessary.
I run Fedora 12, btw.
I'm not even sure which packages are relevant here.
Perhaps these?
 DeviceKit-power-014-2.fc12.x86_64
 gnome-settings-daemon-2.28.2-2.fc12.x86_64