http://www.redmondpie.com/jailbreak-ios-4.2.1-iphone-4-3gs-3g-ipod-touch-4g-3g-2g-with-redsn0w-0.9.6b2-how-to-guide/
Apple today has released iOS 4.2.1 GM for iPhone 4, 3GS, 3G, iPad and iPod touches. This build which is currently available to developers only can be jailbroken using the current version 0.9.6b2 of Redsn0w. For those of you who don’t know, Redsn0w 0.9.6b2 is based on Geohot’s Limera1n exploit which can pwn all iOS devices for life.
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