Ok i was conversing with Marko the author of "Quick Chat" wordpress plugin, and we discovered that guests and regular members can post in quick chat.
But the admin who has access to wp-filebase cannot. What happens is, when you try to post a message by hitting enter, it instead goes to the next paragraph without entering the message. So that is the debug.
It is definitely wp-filebase causing the problem because once disabled, quick chat works fine again.
By the way wp-filebase is not only affecting quick chat, but also light box plus, and oddly enough wp-filebase itself as admin cannot browse the download tree ....
Any ideas how to fix this ? Because i need to use wp-filebase