2 Loops mit random post

<div> 
 <?php if (have_posts()) : ?>
     
     <?php query_posts('showposts=4&cat=6'); ?><?php while (have_posts()) : the_post(); $do_not_duplicate[] = get_the_ID();?>
            
            <a href="<?php the_permalink() ?>"><img src="<?php $values = get_post_custom_values("pft_Thumbnail"); echo $values[0]; ?>" /></a>


            <?php endwhile; ?>


     
     
     
     
     
     <?php 
      $random_query = new WP_Query(array(
      'post__not_in' => $do_not_duplicate, 
      'showposts' => 12, 
      'orderby' => 'rand',
      'cat' => '6'
      ));
      while ($random_query->have_posts()) : $random_query->the_post(); ?>
<a href="<?php the_permalink() ?>"><img src="<?php $values = get_post_custom_values("pft_Thumbnail"); echo $values[0]; ?>" /></a>




    <?php endwhile; ?>


    
         <?php else : ?>


    <?php endif; ?>


   
            
            </div> 


        
            <div id="neuheiten-colright">
                <div id="img-colright">
        


                 <?php query_posts("cat=6&showposts=1"); ?><?php while (have_posts()) : the_post(); ?>
                   <img src="<?php echo(get_post_meta($post->ID, "pft_novelties", true)); ?>" />
            
                </div>
                
                <div id="cont-colright">
                <strong><?php the_title();?></strong>
                <?php the_content($post->ID);?>
                </div>        
                <?php endwhile; ?>