My iPhone (first-gen) died on me. I'm borrowing a friend's old iPhone (also first-gen) until the new one is out next month. My question is... can I perform an iTunes restore and set up his phone with a backup of my phone? That way, I can keep my number and everything. If not, can I swap the sim cards of the phones and do an iTunes restore that way? I don't mind jailbreaking. Thanks!