iphone 3gs was had around 7-8% battery, when I tried charging it thru a USB cable - it worked for like a minute, but then it dint work. It was dead for 4-5 hrs before i came home and tried a wall charger; initially it showed a red symbol, but then it went black - showing it was not charging. It has been dead for 7-8 hrs now. P.S - Although it is an unlocked phone, it is properly unlocked - not the one wherein you have to use blackrain software everytime the phone is off. please help.