iDector by iH8Sn0w is a real easy to use application to tells you if your iPhone 3GS contains the New Bootrom or the Old bootrom. Simply place your 3GS into DFU mode and click the button. Download the app (Windows) from our forum.
<a href="http://dailyiphoneblog.com/2010/06/27/jailbreak-idector-by-ih8sn0w-checks-if-your-iphone-3gs-contains-the-new-bootrom-or-the-old-bootrom/">

[Read the original blog post]
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