Anti-Spam System

I'm sure whoever will be answering this question will know what I'm talking about, if not feel free to click here.

I love the concept of the Anti-Spam system and think it will come in handy but I question if this effects guests? I'd assume it will. I'll just explain my situation to see if there is a scenario that will work. I have the Anti-Spam system active on my website so people are incapable of posting external links (though I also asked whether external meant Forumotion completely or just my website?) however I also have a guest friendly advertisement board which is pretty much where guests can advertise on our Forum and we can do the same with ease, its the kind of thing most RPG sites do, have their advertisement board guest friendly. But as I said, with the Anti-Spam system in place it seems these guests can no longer attach links to other forums, is this true?

Guest shouldn't be able to post link anyways.

This surely hasn't proved to be the case.