Bought a replacement battery for an iBook G4 from FastMac and it would never charge to a level higher than 75% (did the calibration process). Took it in and got the retailer to swap for another FastMac battery and it wouldn't charge higher than 81% - even after 10+ hours. Called AppleCare, they had me reset the power management module and do something with the RAM - but it looks like this isn't going to solve the problem. Charger ring never turns from Orange to Green. Has anyone had a similar experience? I think it's the battery, but before I ask for a replacement for the replacement of the replacement - I'd like to know if it could be the iBook. Seems unusual that two batteries in a row would fail in the same way. Any ideas?