Both the famous redsn0w jailbreak and ultrasn0w unlocking tool can now support iPhone 3GS with the latest version. iPhone Dev Team has just released the tools, although they had previously decided to postpone the release until iPhone OS 3.1 is out. Check out the download instruction here.

We realize we upset some folks (e.g. existing 3GS owners) with our earlier announcement that we wanted to hold onto the 3GS iBoot-family hole until 3.1 was out. Our aim there was to get as many people as possible onboard (within reason of course) before revealing the hole, since Apple will fix it immediately. But all of that became moot when the purplera1n release was made, since it uses the same hole.

ultrasn0w unlockers — You all must remain particularly vigilant against upgrading your basebands, since doing so will kill the unlock (for most phones, there’s no going backwards in baseband version). Apple has gotten very serious with the latest baseband — they’ve removed 180 (!) commands in an effort to cut down their exposure to holes. So please always stay away from stock Apple IPSWs and instead use our tools as we release them. These tools let you update your firmware without updating your baseband.

Those installing ultrasn0w will probably also need to do a single run of Settings->General->Reset->Reset Network Settings. We’re testing various fixes for that particular glitch.

redsn0w platforms — This is the first redsn0w release that also supports linux! It’s the newest version of the bunch, so any feedback would be appreciated. But right now, redsn0w should work on OS X, Windows, and linux.