I've recently discovered a bug which appears to be related to an old topic I found at the US forums:
http://forums.worldofwarcraft.com/thread.html?topicId=79223682&postId=789981095&sid=1#0
Basically, when you create a ScrollFrame "inside" another one (set the ScrollChild of a ScrollFrame to be the parent of another ScrollFrame), the childs of the first stay clickable even when not visible, just like described at that old post.
I posted this issue at the EU forums (
http://forums.wow-europe.com/thread....100819&sid=1#0), but the truth is: Blizzard doesn't really visit them. So, can any US user post it on the US forums for me? It would be really appreciated.
Sorry for the bad explanation,
Jaliborc