Well rewriting this guide every few days as Apple releases a new firmware is becoming a bit much work. Very basic and simple.

1st Generation iphones, are all unlockable regardless of the firmware 1.1.4 as well as 2.x.x (2.1 is the current newest as I am writing this), the bootloader is no problem anymore a program called pwnage is available for mac and pc and makes the unlocking as simple as it can be.

2nd Generation or better know as 3G... well Apple here went the way of locking the IMEI to the serial number, hence a software unlock is basicly impossible. When you launch iTunes the IMEI is checked against the Serial number in Apples data base, 3G iphones bought unlocked like available in Italy or Australia will always remain unlocked as the Serial is registered with Apple as being purchased unlocked. The only way to unlock a 3G iphone is with a man in the middle attack(wrong now apps can do that too)(hence it changes from time to time), or better known as stealth sim attack. A very small piggy back sim is inserted between the original sim and the iphone, to fool itunes into believe this iphone is not lock. I won't go into further detail, Apple pushes the envelope every time they come up with a new firmware to relock and needing redesign of the piggy back sims. This is the main reason why the first generation iphones have kept their value.

Because of restrictions of the 3G iphones 1st generation iphones have hence kept their value, plus the lack of performance due to flawed chip on the 3G has made many users opt not to upgrade.

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