Unlock Iphone 4 4.2.1 firmware 10.03.01 ?

[A.M]

I have an AT&T Iphone 4 4.2.1 firmware 10.03.01 that I'm trying to unlock, can anyone help me how to do it? Also I want to jailbreak it. I want to use the phone with T-Mobile, so I must unlock it!!

[vicecaptain]

Hi, You can unlock an iPhone 4 locked to AT&T network safer and easier through remote unlocking method. It is also an affordable method too. You can get the remote unlocking for an iPhone 4 from www.onlinegsmunlock.com/apple-iphone-4/rs7wp9/ . Once you have unlocked it, You can use your iPhone with any international GSM SIM card.
Here are the steps for unlocking an iPhone 4,
1. Wait for us to send you an email saying your phone has been activated or remotely unlocked.
2. Install the latest version of iTunes.
3. Make sure your Apple iPhone 4 phone software is updated to the latest version using the iTunes software.
4. Connect your Apple iPhone 4 to iTunes with a NOT ACCEPTED SIM card.
5. Wait until iTunes detects your Apple iPhone 4.
6. Disconnect your Apple iPhone 4 and reconnect it after 10 seconds.
7. Your Apple iPhone 4 is now unlocked.