Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_2_1 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8C148 Safari/6533.18.5) Hi, Trying to figure out how to unlock and jailbreak my iPhone 3G to the best version of iOS 4 in terms of speed. Right now, I used PwnageTool (old version) to create a custom unlocked firmware of 3.1.3. However, it hasn't seemed to unlock the firmware and when I try to install ultrasn0w in cydia, it crashes. Tried repeating the process 3 times, but each time I get stalled when cydia crashes and I'm unable to do anything with it. So, I'm going to try upgrading to a version of iOS 4, but need to be able to unlock the device. I know there are problems with 4.2.1 so wondering the best way to go from 3.1.3 to a version of iOS 4. Current baseband is 05.12.01 and 3.1.3 firmware.