iH8sn0w is working on a new version of Sn0wbreeze 2.2 to jailbreak iOS 4.2.1 and will soon be available for download. The updated sn0wbreeze 2.2 will accompany “Baseband Preservation Mode” in addition to simple mode and expert mode to keep the ultrasn0w unlock intact as confirmed by iH8sn0w via tweet. The hacker is currently working hard on GUI upfront and hasn’t cited any ETA so far.
Those who don’t know, Sn0wbreeze is a jailbreaking tool like PwnageTool for iPhone and iPodtouch which can be used to create custom .ipsw files. But unlike the PwnageTool, Sn0wbreeze 2.2 is said to be fully compatible to work with Windows machines without upgrading the baseband allowing you to unlock your iPhone 4, 3GS, 3G on older basebands.
We will update you as and when sn0wbreeze 2.2 is available for download with fully functional tutorial guide.