Thread:Project:Support desk/Short URLs not working after upgrade from 1.19 to 1.23/reply (2)

I'm still not further. What I only see, is that the original URL is processed by mediawiki and for some reason it is redirected to the wrong encoded URL. What PHP variable uses mediawiki to parse the title? Is it $_SERVER['REQUEST_URI']? Is WebRequest::getPathInfo related? I found that it uses parse_url, but this is not UTF8 safe. My IIS/PHP server sets the $_SERVER['REQUEST_URI'] variable with UTF8 encoded URL. It is not escaped.