PwnageTool bundle for iPod touch 4G on iOS 4.2.1 GM has just been released. You can use this bundle with existing version of PwnageTool to create custom firmware file which is jailbroken on the newly released iOS 4.2.1.
If you cant wait for the official tools, you can give this semi-untethered jailbreak method a go! With semi-untethered jailbreak, you will have to reboot your device into the so called “jailbroken state” every time you want to run Cydia.
Download iOS 4.2.1 PwnageTool Bundle for iPod touch 4G
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