Some of the users on the Q&A I built end up responding to posts on their wall by posting on that very same wall. That way, the user replied to does not get a notification.
Someone mentioned that it is somewhat confusing.
I've thought of some ways to deal with this problem :
not dealing with it
add a reply link to wall posts like with comments
when the user gets notified of a wall post by e-mail, add a link to the poster's wall instead of the user's wall (not that great an idea I guess)
Are there any other ideas?