The only solution I found on my Dell Inspiron 2650 was to recompile the kernel after applying the ACPI patch from SourceForge.
Doing this the Gnome windowmanager will have a battery monitor that works, only problem seems to be that it thinks it is on battery all the time.
If you don't want to do that I just watch for my battery light on the laptop to flash orange then I know that the battery is low.
If anybody finds an easier way I sure would like to know, it took me three times recompiling my kernel before I got it working with my mouse
, but I eventually got it to work.