Hm, if i post something, and the right away edit it to change a typo or whatever. Is it the suppose to say "last edited ...". I was thinking thats only if you edit when someone else have posted after your post?

I don't think anyone would like to go through the code just for that a small fix

hm, but do phpforums behave like this or like i think they do?

In phpBB there is a ninja-edit thing where you have something like 30 seconds to edit your post before you get a "Last edited by" thing coming up. In punBB here there is an option for silent edit, but I don't know if that only applies to mods.