As expected untethered jailbreak for iOS 4.2.1 from Chronic Dev Team is now available for download, Greenpois0n RC5 for Mac OS X got released few days ago and today we have Windows version as well letting users untether their jailbreaks.

Much awaited Greenpois0n jailbreaking utility for iDevices is finally available for download, just two days GeoHot surprised everybody by releasing his Limera1n jailbreak capable of pwning all iDevices running iOS 4.1 or later. Unexpected release of Limera1n made Chronic Dev Team and iPhone Dev Team postpone their jailbreaking tools to avoid exposing SHAtter exploit to Apple, Now, Chronic Dev Team has gone ahead with the release of Greenpois0n but without exposing SHAtter and using the GeoHot's already exposed bootrom USB exploit.