--- modules/comment/comment.module.orig	2008-05-07 11:52:58.000000000 +0200
+++ modules/comment/comment.module	2008-05-07 11:56:04.000000000 +0200
@@ -594,7 +594,9 @@ function comment_form_alter(&$form, $for
 function comment_nodeapi(&$node, $op, $arg = 0) {
   switch ($op) {
     case 'load':
-      return db_fetch_array(db_query("SELECT last_comment_timestamp, last_comment_name, comment_count FROM {node_comment_statistics} WHERE nid = %d", $node->nid));
+      if ($node->comment != COMMENT_NODE_DISABLED) {
+        return db_fetch_array(db_query("SELECT last_comment_timestamp, last_comment_name, comment_count FROM {node_comment_statistics} WHERE nid = %d", $node->nid));
+      }
       break;
 
     case 'prepare':