Images have the first letter case-insensitive.
As a result, on wikis with $wgCapitalLinks=false; you can arrive at a different page for the image, with the first letter lowercase, with the image, with no image history, and with edit & upload links, even when the image is not uploadable because the Uppercase image is protected
Compare
http://es.wiktionary.org/wiki/Imagen:wiki.png
http://es.wiktionary.org/wiki/Imagen:Wiki.png
IMHO when viewing the image or image talk namespaces, it should redirect to the upper case one, as if $wgCapitalLinks=true; whatever the site preferences are.
Version: unspecified
Severity: enhancement
URL: http://es.wiktionary.org/wiki/Imagen:wiki.png