iPhone developer iH8sn0w has pushed another update to Sn0wbreeze 2.2, apparently with a new solution to fix iBooks issue for devices on which it previously didn’t work.
I pushed out a small update for sn0wbreeze r3 which fixes iBooks issues for devices that previously didn’t work.
In case you don’t already know, the latest version of both PwnageTool and Sn0wbreeze incorporates kernel based GreenPois0n exploit, which means that you can now create untethered 4.2.1 custom firmware files without the upgraded baseband so that you can unlock with current version of Ultrasn0w.
Simply follow the step by step instructions to create custom 4.2.1 IPSW file without the upgraded baseband to jailbreak your iOS device.
Once you are done with the jailbreak, you can unlock your iPhone 4, 3GS and 3G on the old baseband using Ultrasn0w 1.2.