<p><input name="submit" type="submit" id="submit" tabindex="5" value="<?php esc_attr_e('Submit Comment'); ?>" />
<?php comment_id_fields(); ?>
</p>
-<?php do_action('comment_form', $post->ID); ?>
+<?php
+/** This filter is documented in wp-includes/comment-template.php */
+do_action( 'comment_form', $post->ID );
+?>
</form>