The iPhone 3G with OS 3.0 can now be unlocked using the Ultrasn0w utility from the iPhone dev team. To use this utility your iPhone must be jailbroken using the redsn0w or Pwnage tools (google for more info). Once unlocked, your iPhone can be used with any GSM carrier that uses SIM cards, e.g. T-Mobile.

Please note this will NOT work with iPhone 3G S.

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