If you are owner of an iPhone 3GS and still scratching your head whether your device is jail-breakable or not because of the old bootrom requirement by both redsn0w and Sn0wBreeze here is a simple tool which will tell you whether your iPhone 3GS has the newer bootrom (which is sadly not jailbreakable yet) or the older which can be exploited by redsn0w or sn0wbreeze.

iDetector is a simple and small utility by iH8sn0w which will provide you the answer telling whether your iPhone 3GS has an old bootrom or the new bootrom, to get it working all you need to do is to put your device in DFU mode and click the button 'Is my Bootrom Old or New ?' and you will have the straightforward answer.