Chronic Dev Team has just released a new video about iOS 4.2.1 full untethered jilbreak in action.
iPhone Dev Team’s Redsnow 0.9.7 already can jailbreak iOS 4.2.1 but it has some limitations.This version of Redsnow can jailbreak required SHSH blobs of 4.2b3 which are already saved on Cydia but if you don’t have those SHSH file so you can’t be able to jailbreak your iDevice.
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