How to modify Meta Widget via functions.php

Hi,
I’ve tried to modify the Meta Widget by inserting a hook into the functions.php file.
Doesn’t work.
Is anybody can help me out?
Here is my code

function Widget_NewOne( $args, $instance ) {
		extract($args);
		$title = apply_filters('widget_title', empty($instance['title']) ? __('Meta') : $instance['title'], $instance, $this->id_base);

		echo $before_widget;
		if ( $title )
			echo $before_title . $title . $after_title;
?>

<ul>
			<?php wp_register(); ?>

<li><?php wp_loginout(); ?></li>
			<?php wp_meta(); ?>
			</ul>
<?php
		echo $after_widget;
	}

if ( function_exists('register_sidebar_widget') ){
    register_sidebar_widget('WP_Widget_Meta', 'Widget_NewOne');
}

Thanks.
Mad.