Hehe, you're right, sending all the data back was stupid.. Never thought about it :( It gave me a 404 or some other error (the page didn't load actually) because this variable wasn't set correctly in my settings-file: $wgScriptPath = "/wiki"; I fixed the path and now it works. Just too bad it's not always a page different from the main page. Oh well, i can live with it.
Thanks for the reply, Tom