What is all this talk about the new bootrom 3GS needing to be downgraded?

[Nor*Cal]

I got a new 32GB 3GS (3.1.3) with new bootrom, and simply ran spirit then installed ultrasn0w to unlock it.

I've been reading that it's not possible and that you have to downgrade even though it was a fairly quick process for me.

If I have cydia running fine on my iPhone, would it be safe to assume everything is ok?

 

[apunkrockmonk]

It's not possible to jailbreak 4.0 on a new boot rom 3Gs.

3.1.2 and I believe 3.1.3 are good to go with the new boot rom and spirit.