Wikimedia Bugzilla is closed!

Probably needs a regex entry fixed or added in redirects.conf.

The redirect indeed had a couple problems:
Use to be

    RewriteCond %{HTTP_HOST} ([a-z]+)\.wikimediacommons.(net|info|mobi|eu)
    RewriteRule ^(.*)$ http://commons.wikimedia.org/$1 [R=301,L]

Now is 

    RewriteCond %{HTTP_HOST} ([a-z]+).wikimediacommons.(net|info|mobi|eu|org)
    RewriteRule ^(.*)$ http://commons.wikimedia.org$1 [R=301,L]

Sadly, the rewrites are cached, so it might take a while before the change takes effect. 
However, the problem should be fixed once the cache expires.