Hi,
I'm having the same problems, using the latest version of URL_Rewrite (http://www.microsoft.com/downloads/details.aspx?FamilyID=6c15b777-8d9e-4d99-b359-a98e2c0880f7&displaylang=en) , which should include the nonASCII fix according to the link.But I also tried installing the nonASCII fix (didn't help)
On my wiki url rewriting works fine, except the Letzte_Änderungen and any page using an umlaut. When going to http://paris143.server4you.de/wiki/Spezial:Letzte_Änderungen I'm getting redirected to http://paris143.server4you.de/Wiki/Spezial:Letzte_%C3%83%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3F%3Fnderungen and finally firefox tells me that it has been redirected to often.
When disabling the urlrewrite module in IIS and removing ArticlePath in LocalSettings.php mediawiki makes the link http://paris143.server4you.de/index.php?title=Spezial:Letzte_%C3%84nderungen which works fine. When replacing %C3%84 manually by Ä still everything works.
After enabling URL Rewrite for IIS (still letting arcticlePath unset) the http://paris143.server4you.de/index.php?title=Spezial:Letzte_%C3%84nderungen URL works, but the beautified http://paris143.server4you.de/Spezial:Letzte_Änderungen is redirected to http://paris143.server4you.de/index.php?title=Spezial:Letzte_%C3%83%3Fnderungen which gives me a 404 error.
Is there still a bug in the URL Rewrite Module (which is great by the way), or have I configured something wrongly in my IIS or in PHP.ini?
Any help would be highly appreciated,
Johannes