Iphone 3GS jailbroken and dead. What to do??

[KSKENE247]

I personally have an iphone 4 but my roommate has an iPhone 3Gs that is only a few months old and is jailbroken. One day he woke up and it was dead and would not respond to a charger or being plugged into a computer. I tried the few things I could think of, like hard restarting and things like that but nothing helped. The phone still has a warranty so he can bring it back, but he is scared of them fixing it and finding out that it is jailbroken. Anyone have any hints or ideas? I believe its jailbroken on 4.3
Any help is appreciated.
Thanks!

 

[awadeee]

Try holding the home and power buttons at the same time for 10-15 seconds.