CPT for rewrite rules

<?php
/*
Plugin Name: Custom Post Type Test
Plugin URI: http://zed1.com/
Description: Testing Custom Post Types in WordPress 3.1
Author: Mike Little
Version: 0.1.0
Author URI: http://zed1.com/
License: GPLv2 or later
*/

new cpt(); // kick it all off
register_activation_hook( __FILE__, array( 'cpt', 'activation' ) );
register_deactivation_hook( __FILE__, array( 'cpt', 'deactivation' ) );

class cpt {
    function __construct() {
        add_action( 'init', array( 'cpt', 'init' ) );
    } // end constructor

    static function activation() {
        self::register_cpt();
        self::flush_rules();
    } // end activation

    static function deactivation() {
        self::flush_rules();
    } // end deactivation

    static function flush_rules() {
        flush_rewrite_rules();
    } // end deactivation

    static function init() {
        self::register_cpt();
    } // end init

    static function register_cpt() {
        if ( !post_type_exists( 'cpt' ) ) {
            $labels = array( 'name' => _x( 'CPTs', 'post type general name' ),
                             'singular_name' => _x( 'CPT', 'post type singular name' ),
                             'add_new' => _x( 'New CPT', 'add new singular name' ),
                             'add_new_item' => __( 'Add New CPT' ),
                             'edit_item' => __( 'Edit CPT' ),
                             'new_item' => __( 'New CPT' ),
                             'view_item' => __( 'View CPT' ),
                             'search_items' => __( 'Search CPTs' ),
                             'not_found' =>  __( 'No CPTs Found' ),
                             'not_found_in_trash' => __( 'No CPTs found in Trash' ),
                             'parent_item_colon' => '-:-'
                           );
            $args = array( 'labels' => $labels,
                           'public' => true,
                           'publicly_queryable' => true,
                           'show_ui' => true,
                           'query_var' => true,
                           'rewrite' => array( 'slug' => 'cpt',
                                               'with_front' => true,
                                               'feeds' => false,
                                               'feed' => false,
                                               'pages' => true,
                                               'ep_mask' => 0 //(EP_ROOT)
                                              ),
                           'has_archive' => 'cpts',
                           'capability_type' => 'post',
                           'hierarchical' => true,
                           'show_in_nav_menus' => true,
                           'menu_position' => 100, // last block
                           'supports' => array( 'title',
                                                'editor',
                                                'excerpt',
                                                //'comments',
                                                'revisions',
                                                'page-attributes',
                                                'shortlink' )
                         );
            register_post_type( 'cpt', $args );
        }
    } // end register_cpt

} // end class cpt

/* put this in your side bar
<?php list_cpts(); ?>
*/

function list_cpts( $args = array() ) {
    global $post;
    $default_args = array( 'post_type'=>'cpt', 'title_li'=> __('CPTs') );

    if ( is_single() && ( 'cpt' == $post->post_type ) ) {
        if ( $parent_id = wp_get_post_parent_id( $post->ID ) ) {
            $default_args['child_of'] = $parent_id; // get siblings
        } else {
            $default_args['child_of'] = $post->ID; // get children
        }
    }

    $args = array_merge( $default_args, $args );
    return wp_list_pages( $args );
}