Finally! You can Jailbreak your iPhone on OS 3.0 Using RedSn0w (Windows)!
What is RedSn0w?
redsn0w is an easy to use, multi-platform, multi-device jailbreaking and unlocking (iPhone 2G only) tool for the iPhone 2G (original iPhone), the iPhone 3G (but not the 3GS) and also the iPod touch (first and second generation). Currently it is available for Windows and Mac OS X (there are some issues using redsn0w with OS X PPC, please use an Intel Mac until we have this problem resolved).
REDSN0W PROVIDES SIMILAR FUNCTIONALITY TO QUICKPWN.
1. GOLDEN RULE: If you are using a 3G iPhone with yellowsn0w and rely on yellowsn0w to obtain cellular service, then you should NOT use redsn0w right now. Ultrasn0w (the 3G carrier unlock) is not included with this release and therefore your baseband will be locked and unable to use an operator other than the official one it was bought for. UltraSn0w will be released via APT (cydia and icy) soon. If you have an original iPhone (1st generation) then 3.0 carrier unlock works with this redsn0w release.
2. Yellowsn0w in its current form will NOT work with the baseband version that is present in the 3.0 update, you will need Ultrasn0w, which will be released sometime soon, Ultrasn0w will work with all iPhone 3G models (but not 3GS), even ones that were previously unlockable, Ultrasn0w (when available) will be released via APT (this means you will be able to get it via Cydia or Icy).
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 version of redsn0w.
6. This app is suitable for the recent 3.0 release
7. redsn0w will NOT work for the iPhone 3GS.
8. redsn0w WILL work for Original iPhone (1st Generation), Original iPod touch, iPod touch 2G and the iPhone 3G (not the iPhone 3GS).
Watch the video here!
Check out more details @ How to Jailbreak Your iPhone on OS 3.0 Using RedSn0w (Windows)