diff --git a/include/functions_comments.inc.php b/include/functions_comments.inc.php
index d974cbc6..821558a4 100644
--- a/include/functions_comments.inc.php
+++ b/include/functions_comments.inc.php
@@ -204,7 +204,7 @@ function serendipity_displayCommentForm($id, $url = '', $comments = NULL, $data
         'commentform_entry'          => $entry
     );
 
-    if (! isset($commentform_data['required_fields'])) { $commentform_data['required_fields'] = ['name' => false, 'comment' => false]; }
+    if (! isset($commentform_data['required_fields'])) { $commentform_data['required_fields'] = ['name' => false, 'comment' => false, 'email' => false, 'url' => false]; }
 
     $serendipity['smarty']->assign($commentform_data);