So I was trying to update My3G the other day. It hung up and didn't finish so I exited out and now everytime I try to go back into Cydia it's stuck on a Repair screen. Has anyone encountered this problem.
Did you do a hard reset? Press and hold down both the power and home key until the iPhone turns off and the Apple logo reappears. Then release them both. If all else fails restore to 4.0.1 and re-jailbreak with jailbreakme.com