Wirelessly posted (Mozilla/5.0 (iPhone; U; CPU iPhone OS 4_3_5 like Mac OS X; en-us) AppleWebKit/533.17.9 (KHTML, like Gecko) Version/5.0.2 Mobile/8L1 Safari/6533.18.5) So I am from Japan and have an original 2 year contract with softbank. unfortunately with my visit in the US my iPhone fell, cracked, and fail to turn on. I have bought an unlocked white 32gb iPhone 4. Can I just return to Japan, stick my old sim card (from previous iPhone that is now broken) into my new factory unlocked iPhone and expect it to work flawlessly? Thanks in advance.