Roughly 48 hours after news broke that a New Jersey teenager successfully hacked the iPhone and signed up with T-Mobile (effectively breaching Apple's exclusivity deal with AT&T), word came down that modifying your iPhone in such a way would "brick" the iPhone... effectively turning it into a $500 paperweight. That was largely thanks to automatic firmware updates from Apple, incidently.
Now, it has to be noted that a SquareTrade iPhone warranty wouldn't cover software issues. If you were able to find iPhone insurance - which probably costs three times as much - it won't be covered.
That said, we still want to help. Our good friends over at Zolved has posted a step-by-step tutorial on how to reset, restart, and restore your iPhone. There's no guarantee these will work, or that un-bricked iPhones will stay un-bricked past another firmware update, but it won't cost you anything to try.
Of course, the safest thing is to not modify your iPhone, but where's the fun in that?
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