PwnageTool 4.2 for iOS 4.2.1 Untethered Jailbreak Released! [Update While Preserving Baseband]
The iPhone Dev Team has just released official version of PwnageTool 4.2 which incorporates the new kernel based exploit of GreenPois0n for creating full untethered iOS 4.2.1 custom firmware files. Almost all iOS devices are supported except for iPod Touch 2G.
List of supported devices by PwnageTool 4.2 includes:
When to use PwnageTool over GreenPois0n? If your iPhone relies on a carrier unlock, YOU MUST use this version of PwnageTool to create custom 4.2.1 firmware files without the upgraded baseband so that you can unlock your phone on the old baseband using Ultrasn0w 1.2.
Instructions for jailbreaking using PwnageTool are similar to the last release, simply follow them as posted here. Select iOS 4.2.1 IPSW file where required.