Some time ago all images, using any characters with diacritics in name disappeared, images with standard characters work normally - I have 3 instalations of mediawiki on our server and it happens in all of them:
Mediawiki 1.16.4, Apache/2.2.17 (Win32) DAV/2 mod_ssl/2.2.17 OpenSSL/1.0.0a PHP/5.2.17
There is probably some coding problem when storing the images, because images are stored on server, but with wrong names. For example: "Letňany.jpg" is stored as "LetĹany.JPG".
Thank you for any ideas.