Hello ,
I have iPhone 4:
Version 4.1 8b117
carrier carrier lab 8.0
model mc608ll
modem firmware 02.10.04
jilbroken and unlock with gavy sim
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iPhone 3gs
Version 4.1 8b117
carrier carrier 8.0
model mc64oll
modem firmware 06.15.00
jilbroken and unlock software and the iPhone is able to be shut down and turn off and on with no problem