The Dev Team has released PwnageTool and QuickPwn (for both the Mac and PC) 2.2.5. Below gives you the general idea about the jailbreak for firmware 2.2.1 but, you will want to check out the Dev Team’s website to see all the info (there is a lot more) and to get the links to the jailbreaks.
If your iPhone is unlocked…or you would like it to be unlocked it the future…do not upgrade to firmware 2.2.1.
“This is the low down on our tools for use with the 2.2.1 firmare from Apple, read the whole post in full before attempting anything.
1. GOLDEN RULE: If you have a 3G iPhone running 2.2 firmware and you want to keep your ability to use yellowns0w (or the option to use it in the future) do NOT use QuickPwn, and do not use the official ipsw or the iTunes update process without using PwnageTool.
2. Yellowsn0w will NOT work with the baseband version (02.30.03) that is present in the recent 2.2.1 update – you will need to create a custom ipsw that will allow you to update safely without affecting the baseband.
3. Please read all parts of this post before downloading and using these tools.
4. Read items 1, 2 and 3 again and again.
5. At the bottom of this post are the bittorrent files for the latest versions of PwnageTool and QuickPwn.
6. These apps are suitable for the recent 2.2.1 release.
7. The Yellowsn0w version has been updated to 0.9.7. Yellowsn0w is available from Cydia or Installer – this version allows compatibility with pwned 2.2.1 system (not baseband) – again – remember 0.9.7 yellowsn0w DOES NOT WORK WITH 2.2.1 (02.30.03) directly – you need to be running a ‘pwned’ version of 2.2.1 which doesn’t upgrade the baseband.
8. Users of OS X 10.5.6 will be unable to use DFU mode correctly, please see the note towards the end of this post to easily fix this issue.”
Click HERE for the rest of the article.