Please be informed that it is an advanced level hack so only proceed if you have a good understanding of what you are doing. It is strongly recommend for users with unlocked iPhones to wait till the iPhone Dev team releases a patch for the new firmware. Or if you are a risk taker, then you may proceed at your own choice. I am not responsible in anyway.. haha
Following procedure is applicable for those with a AT&T locked iPhone and all iPod Touch users.
Installing iPhone 3.0 beta on the iPhone
- Make sure to have downloaded the iPhone 3.0 beta firmware that relates to your iPhone (2G or 3G). You need to register as a develpor with Apple to do so.
- Extract the firmware IPSW to a folder.
- Connect the iPhone to your iTunes.
- Get the UDID registered on the iPhone Developer program. (Google it).
- Open iTunes and click Restore while holding the Shift key (for Windows).
- Browse to the firmware IPSW.
- Wait for iTunes to automatically unpackage and install the firmware.
WARNING: Attempting to do this upgrade on a unlocked iPhone can make it useless forever.
Please note that after upgrading to iPhone 3.0 beta, you might not be able to downgrade to firmware 2.2.1 later on so it is always a wise choice to wait for the official release. It has been found that iPod Touch users are always safe but I have clearly warned the iPhone users to proceed at their own risk.