If you're a legit AT&T user, you can jailbreak 2.2.
If you're an AT&T user, user QuickPwn 2.2 on Windows
http://www.quickpwn.com/2008/11/quic...d-windows.html
Or you can use PwnageTool 2.2 on Macintosh
http://www.iphonehacks.com/2008/11/jailbreakunlock.html
Scroll down the page of the PwnageTool 2.2 in order to find the Download links.
Good luck mate.
PS: If you're wondering what is the difference between Pwnagetool and Quickpwn - PwnageTool gives you a better chance of being able to use any Software Unlock that is released in the future, since your baseband will not be updated, and also you NEED to use PwnageTool if you are not an AT&T user and are using a sim chip (Turbo SIM); on the other hand, if you're an AT&T user you can use QuickPwn but your chances of being able to use a Software Unlock in the future will decrease.