I am buying an iPhone as a gift for someone, and need to get a used one that can have an untethered jailbreak. I know that it needs to have an older version of iBoot, 359.3, but I think many people selling their iPhones on craigslist are not going to check their iBoot version for me. I know most likely iPhones manufactured week 36 or earlier (which would be easier for them to check I assume) have a good chance of being capable of an untethered jailbreak, but it is not a certainty. So how can you be certain a used iPhone can have an untethered jailbreak? If it still has version 3.0 does that guarantee that the iBoot version hasn't been updated? Does modem firmware 04.26.08 not guarantee anymore an untethered jailbreak? I tried to buy one the other day from craigslist. The seller said it was jailbroken. When I met him I noticed it had 3.1.2 and 5.11, and I also saw blackrain. So I tried to power it off to make sure it wasn't a tethered jailbreak. The iPhone would not power off! So I didn't buy it. I am worried people are selling their iPhones as jailbroken and unlocked now, and not telling people that it is a tethered jailbreak. Would this be the best way to tell? Power off and back on again and if it doesn't work anymore, you know it is a tethered? Thanks!