I think the problem comes from there (main template) :
<span class="feedback"> <?php wp_link_pages(); ?> <?php comments_popup_link(__('0 Commentaire'), __('1 Commentaire'), __('% Commentaires')); ?> </span>
</div>
<!--
<?php trackback_rdf(); ?>
-->
<?php comments_template(); ?>
</div> <!-- End Post -->
<?php endforeach; else: ?>
<p><?php _e('Sorry, no posts matched your criteria.'); ?></p>
<?php endif; ?>
<div id="footer">
<p class="credit"><!--<?php echo $wpdb->num_queries; ?> requêtes. <?php timer_stop(1); ?> secondes. --> </p>
</div> <!-- End foot -->
</div> <!-- End Content -->