I'm having a problem with my battery now too. My extended battery died at work so I switched to the original battery (which I haven't used since I got the phone). Then I put my extended battery in and full charged it, it seems to be losing it's charge alot faster than normal. Syncing, wifi, gps, all that is off yet it's still losing it's charge (like 1% every 5-10 mins). Does my phone still think that my original battery is in and not my extended??