filter on custom taxonomies

add_action( 'init', 'create_ressource_fr_post_types' );

function create_ressource_fr_post_types() {
	register_post_type( 'ressource_fr',
		array(
			'labels' => array(
				'name' => __( 'Ressources FR' ),
				'singular_name' => __( 'Ressource FR' ),
				'add_new' => __( 'Ajouter' ),
				'add_new_item' => __( 'Ajouter une nouvelle ressource de français' ),
				'edit' => __( 'Modifier' ),
				'edit_item' => __( 'Modifier une ressource' ),
				'new_item' => __( 'Nouvelle ressource' ),
				'view' => __( 'Afficher la ressource' ),
				'view_item' => __( 'Afficher la ressource' ),
				'search_items' => __( 'Chercher dans les ressources de français' ),
				'not_found' => __( 'Aucune Ressource trouvée' ),
				'not_found_in_trash' => __( 'Pas de ressources trouvée dans la corbeille' ),
				'parent' => __( 'Ressource parent' )
			),
			'public' => true,
			'hierarchical' => true,
			'supports' => array(  'title', 'editor', 'page-attributes' ),
			'query_var' => true,
			'rewrite' => true,
		)
	);
}

add_action( 'init', 'register_profperso_taxonomies', 0 );

function register_profperso_taxonomies() {

	register_taxonomy(
		'classement_fr',
		array( 'ressource_fr' ),
		array(
			'public' => true,
			'hierarchical' => true,
			'labels' => array(
				'name' => __( 'Classements FR' ),
				'singular_name' => __( 'Classement FR' )
			),
			'query_var' => 'classement-fr',
	        'rewrite' => array( 'slug' => 'cours-fr' ),
		)
	);

}

add_action( 'restrict_manage_posts','my_restrict_manage_posts' );

function my_restrict_manage_posts() {
	global $typenow;
	if ($typenow=='ressource_fr')
		wp_dropdown_categories( 'show_option_all=Afficher tout&show_count=1&hierarchical=1&taxonomy=classement_fr&name=classement_fr');

}

add_action( 'request', 'my_request' );
function my_request($request) {
       if (isset($request['post_type']) && $request['post_type']=='ressource_fr') {
               $request['taxonomy'] = 'classement_fr';
               $request['term'] = get_term($request['classement-fr'],'classement_fr')->name;
               unset($request['name']);
       }
       return $request;
}