sn0wbreeze 2.2, the custom jailbreak firmware tool for iOS 4.2.1 has been updated to RC3 which includes a fix for the iBooks issue. It fixes the check that Apple has put for jailbroken devices. A custom firmware made with sn0wbreeze 2.2 RC3 wont see the following error:
The method to jailbreak your iPhone, iPod Touch or iPad with sn0wbreeze 2.2 RC3 is the same as with sn0wbreeze 2.2. Here’s how you can jailbreak your iPhone/iPod touch/iPad with sn0wbreeze 2.2 RC3. Just use the sn0wbreeze 2.2 RC3 version available here for download.
greenpois0n was also updated to with a fix for iBooks to RC6.1. Follow either of these guides to jailbreak your device with iOS 4.2.1:
- How to Jailbreak Verizon iPhone 4 iOS 4.2.6 with greenpois0n RC5.4 [Download + How to Guide]
- How to Jailbreak iOS 4.2.1 Untethered On iPhone 4 With PwnageTool 4.1.3 Custom Bundle
- How to Jailbreak iOS 4.2.1 Untethered On iPhone 4 Without Updating Baseband Via TinyUmbrella [Guide]
- How to Jailbreak iOS 4.2.1 Untethered iPhone 4/3GS, iPad GreenPois0n [Mac OS X] VIDEO GUIDE
- How to Jailbreak iOS 4.2.1 Untethered iPhone 4/3GS, iPad GreenPois0n [Windows]