The new jailbreakMe 2.0, aka Star, has been released by The iPhone Dev Team (comex et al.). This userland method tool jailbreaks all iOS devices including the iPhone 4, iPhone 3GS [new bootrom/old bootrom] and iPhone 3G on iOS 4.0.1.  This tool uses the safari browser from within your iDevice to perform the jailbreak, so naturally no tethering is in order.

However, please note that this tool does not jailbreak iOS 4.1beta. This tool also does not hacktivate your iDevice. You still need the original SIM to activate your iPhone with iTunes. If you don’t have an original SIM, you can follow the link here to activate your device without an original SIM.

How to jailbreak iPhone 4, iPhone 3GS, and iPhone 3G, using JailbreakMe 2.0:

• Start iTunes and backup everything from Contacts, Calendars, Photos, Videos and Apps.
• Update your iPhone 4, 3GS or iPhone 3G on the latest iOS 4.0.1 firmware with iTunes.
• Once you are done with the update, make sure you are connected to a WiFi network.
• Open Safari on your iPhone 4, 3GS or 3G and navigate to http://jailbreakme.com.
• “Slide to Jailbreak” to begin the jailbreak process.
• Wait for the required files to download,

• The jailbreak process starts automatically once the files are downloaded. Please be patient and let the process conclude.

• Once done, you will be greeted with the following message.

• Voila! You should now have cydia on your newly jailbroken iDevice.

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