How can i unlock my iphone?

I've upgraded to the 3GS and given my 3G to a friend in the US to use on the AT&T network (im in the UK). It was currently on the O2 network (not yet unlocked) i understand O2 can unlock it, however this takes 14 days and would like to speed things up a little if possible. So Whats can i do to unlock it and get it working on AT&T?

Thanks.

Source:

http://answers.yahoo.com/question/index?qid=20100115203900AAaFRsL

>Open Question: How can i unlock my iphone?

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