Rewrite for cpt produces 404 for regular posts an pages

Hi,

this is my function regitering my custom post type:

add_action( 'init', 'erfolgsgeschichten_taxonomy_init' );

function erfolgsgeschichten_taxonomy_init() {
	register_taxonomy(
		'erfolgsgeschichten_taxonomy',
		'erfolgsgeschichte',
		array(
			'label' 					=> __( 'Erfolgsg. Kategorien' ),
			'sort' 						=> TRUE,
			'public'            		=> TRUE,
			'query_var'         		=> 'neu-de-erfolgsgeschichten',
			'args' 						=> array( 'orderby' 	=> 'term_order' ),
			'rewrite' 					=> array('slug' => 'neu-de-erfolgsgeschichten'),
		)
	);
}

add_action('init', 'herzklopfen_erfolgsgeschichte_register');

function herzklopfen_erfolgsgeschichte_register() {
	$labels = array(
		'name' => __('Erfolgsgesch.', 'zenon'),
		'singular_name' => __('Erfolgsgeschichte', 'zenon'),
		'add_new' => __('Erstellen', 'zenon'),
		'add_new_item' => __('Erfolgsgeschichte erstellen', 'zenon'),
		'edit_item' => __('Erfolgsgeschichte bearbeiten', 'zenon'),
		'new_item' => __('Neuer Erfolgsgeschichte', 'zenon'),
		'view_item' => __('Ansehen', 'zenon'),
		'search_items' => __('Search Erfolgsgeschichten', 'zenon'),
		'menu_icon' => get_stylesheet_directory_uri() . '/images/backend/microposticon.png',
		'not_found' =>  __('Nothing found', 'zenon'),
		'not_found_in_trash' => __('Nothing found in Trash', 'zenon'),
		'parent_item_colon' => ''
);

	$args = array(
		'labels' => $labels,
		'public' => true,
		'exclude_from_search' => FALSE,
		'publicly_queryable' => TRUE,
		'show_ui' => true,
		'query_var' => true,
		'menu_icon' => get_stylesheet_directory_uri() . '/images/erfolgsgeschichte.png',
		'rewrite' => array
            (
                /*'slug' => '%erfolgsgeschichten_taxonomy%',*/
				'slug' => '/erfolgsgeschichten',
				'with_front' => FALSE
            ),
		'capability_type' => 'post',
		'hierarchical' => false,
		'menu_position' => 6,
		'supports' => array('title','editor','excerpt','thumbnail', 'custom-fields', 'revisions'),
		//'register_meta_box_cb' => 'podcasts_add_meta'
	  ); 

	register_post_type( 'erfolgsgeschichte' , $args );
	global $wp_rewrite;
    $wp_rewrite->flush_rules();
}

add_filter('post_type_link', 'erfolgsgeschichten_permalink_structure', 10, 2);

function erfolgsgeschichten_permalink_structure($post_link, $post){
    if ( false !== strpos( $post_link, '%erfolgsgeschichten_taxonomy%' ) ) {
        $event_type_term = get_the_terms( $post->ID, 'erfolgsgeschichten_taxonomy' );
        $post_link = str_replace( '%erfolgsgeschichten_taxonomy%', array_pop( $event_type_term )->slug, $post_link );
    }
    return $post_link;
}

The rewrite for my custom post types works fine.

All other posts an pages return a 404.

What could be the issue?

Thanks,
Lars