Since my last upgrade to Ubuntu 7.10, the Gnome battery monitor stopped working properly and displayed as if it were always powered on. Surfing the web I found out that this is a problem of the buggy DSDT that Acer ships with their BIOS.
The following is a link that can be the starting point to create a correct DSDT:
Ubuntu Forums - Howto fix ACPI/battery problems
I will continue logging in this blog any progress done.