Unless you’ve been living under a rock for the past few hours, you know that the long awaited GreenPois0n untethered jailbreak for iOS 4.2.1 was finally released.

Maybe it’s just me, but I always seem to run into some sort of problem with missing or broken Cydia installations after a successful jailbreak.

To fix this issue I was able to install RedSn0w 0.9.6 on top of my GreenPois0n jailbreak with no ill results. By doing this you will still retain your untethered jailbreak, while gaining the necessary Cydia icon.

Check inside for the full video walkthrough…

Once you successfully jailbreak your iPhone with GreenPois0n using this tutorial, simply follow the instructions laid out in the video to install RedSn0w on top of your GreenPois0n installation in order to gain your missing Cydia icon.

Obviously there will be other ways to accomplish the same thing, but this was the way I was able to do so, and it was successful.

If you’re a RedSn0w user, you can probably do this in your sleep already. If you’re new to RedSn0w, you can find our tutorial for that tool here.

Both GreenPois0n and Redsn0w can be downloaded via our downloads section.

What do you think?