I have a 3GS on 4.1 I am trying to upgrade to 4.3.3 and am having problems with. If I can't get the 4.3.3 update to work correctly, what is the easiest way to jailbreak 4.1? Is it Greenpois0n? Also, I bought this from someone else who hadn't updated it yet and I no longer have the 4.1 ipsw file on my computer. Will I need to download that or will the jailbreak work without it?