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Well the question is basically in the title: I just got my new iphone 3GS and I want to jailbreak, however I do not know if it has the new bootloader. It is on version 3.1.2. If you need other information just ask.

Thanks in advance,
King Mook Mook

Put it in DFU mode and plug it into a Mac
Then go to About this Mac and click on More Info, then USB, will give bootrom version.
 
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