Downgrade iPhone 06.15.00 Baseband to 05.13.xx[How To]
A new method to downgrade iPhone 3G 06.15.00 Baseband to 05.13.xx is available now.It will enable you to restore your device on the official stock firmware using iTunes which was otherwise not possible on iPad’s 06.15.00 baseband.This method currently only works with the iPhone 3G with bootloader 5.8.The procedure is straightforward.It is also highly recommend you to backup everything on your device before following the procedure.