-define( 'CONTENT_FORMAT_WIKITEXT', 1 ); // wikitext
-define( 'CONTENT_FORMAT_JAVASCRIPT', 2 ); // for js pages
-define( 'CONTENT_FORMAT_CSS', 3 ); // for css pages
-define( 'CONTENT_FORMAT_TEXT', 4 ); // for future use, e.g. with some plain-html messages.
-define( 'CONTENT_FORMAT_HTML', 5 ); // for future use, e.g. with some plain-html messages.
-define( 'CONTENT_FORMAT_SERIALIZED', 11 ); // for future use with the api, and for use by extensions
-define( 'CONTENT_FORMAT_JSON', 12 ); // for future use with the api, and for use by extensions
-define( 'CONTENT_FORMAT_XML', 13 ); // for future use with the api, and for use by extensions
+define( 'CONTENT_FORMAT_WIKITEXT', 'text/x-wiki' ); // wikitext
+define( 'CONTENT_FORMAT_JAVASCRIPT', 'text/javascript' ); // for js pages
+define( 'CONTENT_FORMAT_CSS', 'text/css' ); // for css pages
+define( 'CONTENT_FORMAT_TEXT', 'text/plain' ); // for future use, e.g. with some plain-html messages.
+define( 'CONTENT_FORMAT_HTML', 'text/html' ); // for future use, e.g. with some plain-html messages.
+define( 'CONTENT_FORMAT_SERIALIZED', 'application/vnd.php.serialized' ); // for future use with the api, and for use by extensions
+define( 'CONTENT_FORMAT_JSON', 'application/json' ); // for future use with the api, and for use by extensions
+define( 'CONTENT_FORMAT_XML', 'application/xml' ); // for future use with the api, and for use by extensions