I just got this iPhone 3G that has been jailbroken with Ultrasn0w and is connecting to Wifi, its running 4.1 (8B117), the firmware spot is blank so I dot know the baseband. When I put a sim card in it (AT&T) it just says searching and nothing happens. When I go to network the cell where it says tethering looks like its loading but nothing. I've tried to restart it with the sim card in it and tried a cold restart also. I have no idea what else has been done! Please help , any advice will be greaty appreciated! p.s. Also the phone is SUPER slow! If you have any advice as to how to get it to speed up it'll be awesome! Thanks in advance!