list links in same category (something wrong)

Hi,
In the single.php, I want to show the recent posts in the same category (each post has single category in my wordpress) as the post story. Here is my code:

<h4>Recent stories in the <?php the_category(', ') ?> category</h4>
	<ul>
	<?php
	global $post;
	$category_posts = get_posts('numberposts=5&offset=1&category_name=<?php the_category(', ') ?>');
	foreach($category_posts as $post) :
	?>
	<li><a href="<?php the_permalink(); ?>"><?php the_title(); ?></a></li>
	<?php endforeach; ?>
</ul>

However, the list that I got is the first category in my wordpress database, not the same category as show in my <h4>. Can anyone tell my what I did wrong in my code?