I have an iBook G4 purchased in October of 2005. I recently noticed the battery was providing less and less of charge, so I purchased a new battery last week. However, when the new battery is charging, the ring on the power adapter stays amber for a few minutes and then starts rapidly blinking green and amber. Charging this new battery, consequently, is taking several hours. My power adapter works fine with my PowerBook, so I don't think this problem is connected to the adapter. I've tried calibrating the battery, but I think the problem could be something larger. Does anyone have any advice? Thanks.