Guys, if you have a factory unlocked Iphone 3GS with the latest bootroom, i.e. 3.1.3. and wished to install some marvellous apps from Cydia but you can't, do not despair!!!
I have found a website using Spirit to jailbreak your latest 3GS with the latest bootrom and it works for me! What you need to do right now is to point your browser here and make sure you follow the instructions!