ist ja eigentlich schon alles gesagt.
ein paar Basics zum Thema stehen hier:
http://www.heise.de/mac-and-i/artike...t-1176447.html
geht auch mit IOS 4.3.3 auf dem iPhone 4 und dem iPad2.
Also nicht updaten auf IOS 4.3.4 oder IOS 4.3.5
In Cydia steht unter dem Punkt "Upgrading"
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Don't upgrade abobe iOS 4.3.3
As of September 25, 2011
Apple recently released iOS firmware version 4.3.4 and 4.3.5, which
do not have untethered jailbreaks. If you see the pop-up box in iTunes asking you to update your device: ... click
Cancel! Upgrading your device to iOS firmware version 4.3.4 or 4.3.5 will un-jailbreak it, and you will not be able to easily jailbreak your device again (unless a new untethered jailbreak becomes available, which will take an unknown amount of time).
The changes in 4.3.4 are fixes for holes used for jailbreaking, so you don't need this update -- just make sure to install PDF Patcher 2. 4.3.5 fixes a SSL vulnerability, so people on earlier versions should install isslfix.
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