<?php dp_attachment_image($post->ID, 'full', 'alt="' . $post->post_title . '"'); ?>

                   <?php if( get_post_meta($post->ID, "thumbnail", true) ): ?>
                    <a href="<?php the_permalink() ?>" rel="bookmark"><img style="float:left;margin:0px 10px 0px 0px;" src="<?php echo get_post_meta($post->ID, "thumbnail", true); ?>" alt="<?php the_title(); ?>" width="248" height="163"/></a>
                <?php else: ?>
                       <a href="<?php the_permalink() ?>" rel="bookmark"><img style="float:left;margin:0px 10px 0px 0px;"  src="http://www.filmschoolrejects.com/images/frenzy.thumbnail.png" alt="<?php the_title(); ?>"  width="248" height="163"/></a>
                <?php endif; ?>