okimann

You need to reset the query, so a full working code would be:

<?php
	query_posts('cat=5');
	if (have_posts()) : while (have_posts()) : the_post();
	echo('<li><a href="');
	the_permalink();
	echo('">');
	the_title();
	echo('</a></li>');
	endwhile; endif;

	//Reset Query
	wp_reset_query();
?>

And that should do it. You can see this article in the Codex for more info