diff --git a/includes/common.inc b/includes/common.inc
index 5b250da..600e20d 100644
--- a/includes/common.inc
+++ b/includes/common.inc
@@ -1379,6 +1379,21 @@ function format_date($timestamp, $type = 'medium', $format = '', $timezone = NUL
 }
 
 /**
+ * Formats a comment adding rel="nofollow" in each anchor 
+ *
+ * It helps reducing the possibility of being attacked by a comment spammer bot. Plus a 
+ * recommendation by Google at http://www.google.com/support/webmasters/bin/answer.py?answer=96569
+ * 
+ * @param $comment
+ *   The comment to be formatted 
+ * @return
+ *   A formatted comment 
+ */
+function format_comment($comment) {
+  return preg_replace('/(<a\b[^><]*)>/i', '$1 rel="nofollow">', $comment);
+}
+
+/**
  * @} End of "defgroup format".
  */
 
diff --git a/modules/comment/comment.module b/modules/comment/comment.module
index e9fa1e5..2a374c1 100644
--- a/modules/comment/comment.module
+++ b/modules/comment/comment.module
@@ -1688,7 +1688,7 @@ function template_preprocess_comment(&$variables) {
   $comment = $variables['comment'];
   $node = $variables['node'];
   $variables['author']    = theme('username', $comment);
-  $variables['content']   = $comment->comment;
+  $variables['content']   = format_comment($comment->comment);
   $variables['date']      = format_date($comment->timestamp);
   $variables['links']     = isset($variables['links']) ? theme('links', $variables['links']) : '';
   $variables['new']       = $comment->new ? t('new') : '';