One of the steps I read in the jailbreaking tutorials is to download the latest firmware 4.3.3. and to point to it when option-clicking the restore button in iTunes. Do I have to perform this step if my iphone 3GS already has already been updated to this firmware? Or can I skip directly to the next step, which is to launch redsnOw? This will be the first time I've jailbroken an iphone. I'm not interested in unlocking it. The file iPhone2,1_4.3.3_8J2_Restore.ispw is also already on my iMac in Library/iTunes/iPhone Software Updates.