Comex has a untethered jailbreak working for iOS 4.2.1. We still don’t know when it will be released to the public, but progress is being made.
The video shows a jailbroken iPhone 4G with iOS 4.2.1 booting without the use of a computer, meaning it’s untethered.
In the meantime, redsn0w already gives tethered jailbreak for 4.2.1

















I really need to update my 3G. Its jail broken, but when Apple came out with the multitasking update it made my phone real slow.
Yes, I suppose that is the case on all 3g iphones, mine was that way also. Multitasking does work well on the 3GS.
In this case Apple was correct for not including multitasking on the 3G because the hardware does not allow for a good user experience with multitasking. I recommend disabling the multitasking and upgrading to at least a 3GS.
waiting for it. I really so need it. iOS is amazing but not tethered jailbroken.
Just to confirm, untethered JB is not available for PC yet?
who care about progress crap – release already!!!! we are all tired of hearing it is coming – so is the end of the world…..