Re: Problem with 2.1 - Error while saving a wiki page
I have seen this before and the problem seems to stem from the "&saved_msg=y" portion of the URL. I'm wondering if this is an AJAX problem.
Try disabling AJAX (under experimental features) and see if the problem goes away. If you already have AJAX disabled then you can probably ignore everything I said. 
;){kind=link}
;){kind=link}