Paging funktioniert nicht

<?php get_header(); ?>
	
	<?php if (have_posts()) : ?>
	
		<div id="container_content">
			<?php
   if (is_home()) {
      query_posts("cat=-31");
   }
?>
			<?php while (have_posts()) : the_post(); ?>
			<div class="container_content_posting">
				 <span class="text_time"><?php the_time('j. F Y') ?></span><br />
				 		
				 		<span class="text_category"><?php   
$catlist = ""; 
$postcats = get_the_category();   
if ($postcats) {   
   foreach($postcats as $the_cat) {   
      $catlist .= $the_cat->name . ' & ';    
   } 
   if($catlist != "") { 
     $catlist = substr($catlist, 0, -3); 
   } 
   echo $catlist; 
}   
?></span><span class="text_title"><?php the_title(); ?></span><br />
				 		<span class="text_tags">
				 			<?php st_the_tags(); ?>
				 		</span>
                     		
                     		<?php the_content('Den ganzen Beitrag lesen »'); ?>
				
		 						<!--<?php trackback_rdf(); ?>-->
		 						</div>
		 							<?php endwhile; ?>
		 							<?php next_posts_link('&laquo; Vorherige Eintr&auml;ge') ?>
			<?php previous_posts_link('N&auml;chste Eintr&auml;ge &raquo;') ?>
		</div>
		
		


		<div id="container_sidebar">


				<?php else : ?>


				Nicht gefunden
		
				<?php include (TEMPLATEPATH . "/searchform.php"); ?>


				<?php endif; ?>


			<?php get_sidebar(); ?>
		</div>
		<br style="clear:both;float:none;" />
		
<?php get_footer(); ?>
</div>