I had an ugly issue with my current gutsy setup. The power manager did not recognise my battery state of my laptop. I was googling around to see that there are lots of people having the same problem. I finally found a resolution for this issue.
Install the sysv-rc-conf utility using synaptic or apt-get. Afterwards run „sudo sysv-rc-conf -p“ command and edit all entries of the hal subsystem which are like S## to S99, quit and restart your computer. Afterwards all runs fine.
The problem is that with some update of gutsy the startup of hal in sysv-init process was moved to a lower level so that the gnome-power-manager was not able to get any information about the battery stats which have been ok if you looked at /proc/acpi/battery…
You can test restarting the hal service manually, if it works afterwards make the above mentioned changes to get it fixed for reboot. Prior keywords for this issue: /etc/inid.d/dbus restart, gnome-power-manager –verbose –no-daemon.
I will post this also to the ubuntu users forum. The resolution for this issues was found here, thanks to Sam Peterson. If there is anybody out there who has contact to the guys maintaining ubuntu maybe you can post that to the folk to avoid this with further updates.