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The unlocking process is so easy you may as well buy a new one and do it yourself.
 
thanks for the advice guys. I'm off to the far east (thailand) next Sunday, and was thinking of buying one there. What potential problems might I have if I proceed and buy one?
 
I think that you should buy a normal original iPhone without anything done to it. This means you can start off from scratch with the Jailbreak process (even using ZiPHone to do it). Also means, you can restore it back to normal as much as possible if anything goes wrong.
 
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