Got a bit of a problem with my 3GS... The battery ran out earlier today so I plugged it in to charge, and got the 'low battery + charging' screen. 15 minutes later the iPhone seemed to be ready to start up having been recharged sufficient amount... except that instead of going into the unlock screen, the spinning circle logo appeared and the phone restarted... Only to go back into the 'low battery + charging' screen again! And again. And again..... Can someone help please??