My battery level always shows up as something like 55% remaining or 63% remaining ...etc despite that it is in fact charging. Additionally it doesn't go any further than 80% remaining even if I keep it in charge forever.

This leads me to a side annoying effect which is that I cannot proceed to install Windows 7 Service Pack 1 as its installer requires the laptop to be plugged with a power cord. My laptop is plugged with the power cord but because of the above issue (it doesn't display anything else than the xx% remaining) Windows thinks that the laptop is using its battery and that the power cord is disconnected.

I have installed the original acer ePower Management tool that let you configure the power scheme... etc, I was hoping that this would help me circumvent the 80% issue but it doesn't.