again. it doesnt matter. they just use the same stuff as 3.1.3
4.1 is jailbroken too. cause they dont need to change anything.
This is not a jailbreak for iPhone OS 4.0. This is a jailbreak-train upgrade of an already jailbroken iPhone to a custom 4.0 firmware. This is not a new jailbreak, and only will work for people whose phones were jailbroken on 3.1.2 or earlier and have not since been upgraded to a stock firmware. It will not work on a new phone that ships with 4.0 or on a phone that's already been upgraded to 4.0.
What if I used RedSnow to unlock and jailbreak, I'm going to guess yes, but just wanted some confirmation.
3.1.3 isn't jailbroken