No, but iTunes does do a back up of all required data on the phone, which if you restore any other phone and connect it, you and place the data from that backup on that phone(s).
If you need a firmware, you can download it via iTunes, or search your hard drive for the ipsw files, as previous firmware versions are stored locally.
the reason I ask is because in italy and australia you can buy an unlocked iphone 3G. SO if you could copy the firmware from an unlocked phone to a US locked phone.....
the reason I ask is because in italy and australia you can buy an unlocked iphone 3G. SO if you could copy the firmware from an unlocked phone to a US locked phone.....