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iOS 4.2.1 Jailbreak Available with redsn0w 0.9.6b4 — just don’t leave your house

Less than 24 hours after iOS 4.2.1 was released for the iFamily, including the hotly-awaited iPad update which brings multitasking and AirPrint/AirPlay functionality, the Dev-Team has whipped up the latest batch of jailbreak for your consuming pleasure. While Cydia and MobileSubstrate have been updated and patched to work with the newest jailbreak build, this release is a Tethered release, which means that if you need to restart or power off your device, you will need to plug it into a computer and re-jailbreak it again to get it working. I remember this from the days of iOS 3.1.2, and it was quite a hassle, let me tell you.
That being said, I have jailbroken my iPad, which doesn’t often leave the house, and it’s working like butter. Magic butter.
Check out all the details at the Dev-Team blog.