My brother has an iPhone 3G which I've owned for a year now. Data has been fine when I had my T-Mobile sim in it, but whenever he put his T-Mob sim in it, the 3G icon is shown, but nothing actually loads. Here are the setting I am using in, well, settings: Please Register or Log in to view images I switched the sim card into a different phone, and mobile internet works with that phone, but not with the iPhone. I jailbroke through redsn0w and unlocked using ultrasn0w. Firmware 4.0 final. Than you for your time.