Hello. I have a 12'' PB Rev A. and have had it for about 8 months or so. All of a sudden, my battery (or something in the software) has been acting weird. I no longer get the warning that you computer is running onlow battery, or whatever it says. It just goes to sleep automatically. It usually happens when it gets around 10%, but really when it wants to go to sleep, it goes to sleep. No warning. I tried resetting the the Power Management Unit, and repaired permissions as well. I checked apple's website for any info, but couldn't find anything other than PMU info. Anyone else have any suggestions as to what might be causing this problem?