Setup Nginx for Mediawiki

Two weeks ago, I migrated a server from Apache/mod_php to nginx/php-fpm. Only today did i succeed to remove all side effects. The latest one:

Static files must not go through php-fpm, but a simple test on extensions is ineffective, as url like http://server/File:name_of_the_file.png must be processed by PHP.

Here is my final setup, that corrects all the errors I encountered:

 server {
     listen 80;
     server_name server_name;
     index index.php;
     root /path/to/www/;

     # Serve static files with a far future expiration
     # date for browser caches
     location ^~ /images/ {
         expires 1y;
     }
     location ^~ /skins/ {
         expires 1y;
     }

     # Pass the request to php-cgi
     location / {
         fastcgi_pass 127.0.0.1:9000;
         fastcgi_param  SCRIPT_FILENAME $document_root/index.php;
         fastcgi_index  index.php;
         include fastcgi_params;
     }
 }