[gpm] how to control low battery notification

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

I'm using fedora 10 containing 
  gnome-power-manager.x86_64                  2.24.2-2.fc10
It used to pop up a notification when the battery dropped below 30%
and now no longer does.  I don't know what I did to disable this, but
I'd like to enable it again.
In fact, it would be nice to be able to set several such thresholds
for notification.
I don't see any control for this in the preferences.
The doc seems to suggest (I could be misinterpreting) that editing 
 /root/.gconf/apps/gnome-power-manager/notify/%gconf.xml
is the solution, and I've tried that but so far with no effect.
I notice that editing preferences does change neighboring files,
but when I try strace gnome-power-manager I don't see these files
being read.
Before I get too far into trying to read the source (which seems to
be for a newer version than I have installed), it occurs to me that
I should try just asking...
Can someone tell me the solution?
Thanks.