Whenever you use the non-shortened URL, it says "No Article Found".
Note that on German Wikipedia, this happens on EVERY file description page, because they a linked with additional URL parameters for FlaggedRevisions (e.g. http://de.m.wikipedia.org/w/index.php?title=Datei:STS-133_patch.png&filetimestamp=20110203184548 ).
Version: .5
Severity: major
URL: http://en.m.wikipedia.org/w/index.php?title=Foobar