Het is me bijna gelukt om een parent aan mijn custom post type te koppelen.

register_post_type( 'features', 			array( 				'labels' => array( 					'name' => __( 'Features' ), 					'singular_name' => __( 'Feature' ), 					'add_new' => __( 'Add Feature' ), 					'add_new_item' => __( 'Add new feature' ), 					'edit_item' => __( 'Edit Feature' ), 					'new_item' => __( 'New Feature' ), 					'view_item' => __( 'View Feature' ), 					'search_items' => __( 'Search Features' ), 					'not_found' => __( 'No Feature found' ), 					'not_found_in_trash' => __( 'No Features Found in Trash' ), 					'parent_item_colon' => __( 'Page' ), 				), 			'public' => true, 			'has_archive' => false, 			'rewrite' => array( 'slug' => 'features', 'with_front' => true, 'hierarchical' => true ), 			'show_in_nav_menus' => false, 			'hierarchical' => true, 			'supports' => array('title','page-attributes'),  		) 		);

Alleen krijg ik met deze instelling de link http://example.com/features/features/mijn-custom-post-title/ ipv http://example.com/features/mijn-custom-post-title/