Untethered Jailbreak for all iDevices on 4.2.1 out now : Greenpois0n
The Chronic-Dev team has delivered. Those waiting for a unthetered solution to the jailbreak of version 4.2.1 on their iOS devices can breathe a sigh of relief.
Also note if you want to unlock the device don’t update to 4.2.1 just as yet.
For all those with already unlocked devices we will have a Guide soon.
Source : Greenpois0n.com