The so called PwnageTool for Apple Macintosh computers was released a while ago that could be used to jailbreak the Apple iPhone which makes it possible to install third party applications on the iPhone. Users should not confuse jailbreaking with unlocking the iPhone. Unlocking would mean that it would be possible to use another phone provider with the iPhone.
The WinPwn software is compatible with Windows XP and Windows Vista 32/64 bit and users have to make sure to uninstall any previous version of the software and that a compatible version of iTunes, that is iTunes 7.7, is installed on the system.
The Apple iPhone Apps website published a detailed walkthrough of the process that it takes to jailbreak the iPhone under Windows and it is probably a good idea to use it for guidance.

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