diff --git a/modules/user/user.module b/modules/user/user.module
index 5ada13d..c6871d8 100644
--- a/modules/user/user.module
+++ b/modules/user/user.module
@@ -2033,7 +2033,7 @@ function user_comment(&$comment, $op) {
   // Validate signature.
   if ($op == 'view') {
     if (variable_get('user_signatures', 0) && !empty($comment->signature)) {
-      $comment->signature = check_markup($comment->signature, $comment->format);
+      $comment->signature = check_markup($comment->signature, $comment->format, FALSE);
     }
     else {
       $comment->signature = '';