Url rewrite problem

But after saving a page. is an error in the url to stand. so there is a 404 page. The text is saved.

This is de full url with the (xdebug) error.

http://stefandebruin.eu/over-mij/%3Cpre%20class=’xdebug-var-dump’%20dir=’ltr’%3E%3Csmall%3Estring%3C/small%3E%20%3Cfont%20color=’#cc0000′>’a'</font&gt; <i>(length=1)</i>http://stefandebruin.eu/over-mij/edit/?message=1

http://ww.wp.xz.cn/plugins/wp-front-end-editor/

https://ww.wp.xz.cn/plugins/wp-front-end-editor/