Jailbreak iPhone 4, 3GS on iOS 4.1 with Limera1n

[dojran]

Moments ago, we posted that Limera1n was released to jailbreak all iOS 4.1
devices forever. We promised with how-to guides and here we go, you can now use the step by step guide below to jailbreak iPhone 4 and iPhone 3GS using Limera1n on Windows only.


Here's the instructions to jailbreak iPhone 4, 3GS on iOS 4.1 using Limera1n, PLEASE read the important notes at the end of the post:

STEP 1: Download Limera1n for Windows from here.

STEP 2: Connect your iPhone to your PC via USB then launch Limera1n and hit “make it ra1n”

STEP 3: You will have to get your device into DFU mode by following the steps on the screen shown by Limera1n.
You iPhone will now be placed in recovery mode.

Press both the power and the home buttons.

When Limera1n asks you to, release the power button.

Your phone will now be in DFU mode

STEP 4: Now, Limera1n app should be shown on your iPhone's home screen. Limera1n will pwn your device forever now.

STEP 5: The jailbreak should be done now. Tap on the limera1n icon on your device and install Cydia.

IMPORTANT:
You have to keep some points in your mind, first, Limera1n will not unlock your device (i.e. you will lose unlock if you upgraded to iOS 4.1 and used limera1n).

Second, Limera1n is not working with old bootrom devices and it doesn't support iOS 4.2 beta, Geohot is fixing the issues right now. Stay tuned.

Limera1n would mess up GreenPois0n jailbreak release as the teams don't want to give Apple two exploits. They would better save one of them to 5th-generation devices.

[dojran]

Warning for Limera1n soft !!
this is a warning given by the dev-team:


After a few very dramatic days in the jailbreak community, geohot has come out of nowhere to release limera1n. It’s a bootrom-level jailbreak that works on the iPhone3GS, iPhone4, iPod touch 3G, iPod touch 4G, the iPad, and (technically) the AppleTV 2G.

DO NOT USE LIMERA1N IF YOU USE THE ULTRASN0W CARRIER UNLOCK — wait for PwnageTool to incorporate the limera1n exploit. This is so that you can avoid updating your baseband and losing the unlock (possibly forever).

Limera1n uses a different exploit than SHAtter, and in fact covers more devices. Although some may question geohot’s dramatic and competitive style, he obviously does have considerable skill pulling this together in just over a day (although he’s had the underlying exploit for months). Credit also goes to @comex, who provides the untethered aspect of limera1n via another one of his growing list of kernel hacks.

The release of limera1n has (hopefully!) averted the burning of 2 bootrom holes at once (both his and SHAtter). Releasing SHAtter now would be a complete waste of a perfectly good bootrom hole in light of limera1n, and so it can be held until Apple closes limera1n’s hole. While there’s no guarantee that Apple won’t also close SHAtter by then, it provides a ray of hope for devices after Apple’s bootrom respin. Meanwhile, look for an alternate implementation of the limera1n exploit in greenpois0n (and possibly other tools), where it should undergo more testing too.

Limera1n wasn’t tested very thoroughly and does have some issues. Geohot typically works these out in subsequent (and rapid) releases. In the meantime, feel free to discuss any problems and their solutions in our comments section.