<?php the_permalink(); ?> funktioniert nicht richtig

<?php $the_query = new WP_Query('cat=-' .$catid. '&showposts=15&offset=0&orderby=post_date&order=desc');
			
					while ($the_query->have_posts()) : $the_query->the_post();


					$do_not_duplicate = $post->ID; ?>
					
					<div class="home_recent_post">
					
<a href="<?php the_permalink(); ?>" rel="bookmark" title="<?php the_excerpt(); ?>"><?php the_thumb(); ?></a>	
						
						<div class="home_recent_title" id="post-<?php the_ID(); ?>">&nbsp;&nbsp;&nbsp;
                        
                                                    							<a href="<?php the_permalink(); ?>" rel="bookmark" title="<?php the_excerpt(); ?>"><?php the_title(); ?></a>
						</div>
                        						</div>

<?php
/*
Plugin Name: Automatic Post Thumb2
Plugin URI: http://devolux.org/post-thumb
Description: The plugin generates a thumbnail from the first image uploaded to a post.
Author: Devolux
Version: 1.0
Author URI: http://devolux.org/
*/


function post_thumb2() {
        global $id, $wpdb;


        //reading from database
        $image_data = $wpdb->get_results("SELECT guid, post_content, post_mime_type, post_title
        FROM $wpdb->posts
        WHERE post_type = 'attachment' && post_parent = $id && post_mime_type LIKE '%image%'
        ORDER BY ID ASC");


$first_image_data = array ($image_data[0]);


        //array output
        foreach($first_image_data as $output) {




                        //if there is no description use title (filename) instead
                        if (empty($output->post_content) == TRUE)
                                  {$output->post_content = $output->post_content;}


                        //images
                        if (substr($output->post_mime_type, 0, 5) == 'image')
                                 {echo "$output->guid \n";}


                        else
                                 {echo '/wp-content/plugins/post_thumb/wp_default.png';}


                                             }
}


?>