--- ./modules/chess/chess.module	2011-02-13 17:36:01.000000000 +0100
+++ ./modules/chess/chess.module.fix_undo	2011-02-13 17:35:53.000000000 +0100
@@ -408,8 +408,8 @@ function chess_view($node, $teaser = FAL
           '#weight' => 5
         );
       }
-      // Not showing move-form, so check for undo-form
-      elseif ($game_info['number_of_moves'] > 0) {
+      // Not showing move-form, so check for undo-form (settings + enough moves made?)
+      elseif ((variable_get('allow_move_editing', 'FALSE') == 'TRUE') && ($game_info['number_of_moves'] > 0)) {
         // check if the last move was made by the current user
         $last_mover = ($next_move == CHESS_LIGHT) ? $game_info['user_black'] : $game_info['user_white'];
         if ($last_mover == $viewer) {