Index: comment.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/comment/comment.module,v
retrieving revision 1.525
diff -u -r1.525 comment.module
--- comment.module      15 Feb 2007 11:40:18 -0000      1.525
+++ comment.module      27 Feb 2007 20:15:40 -0000
@@ -593,6 +593,9 @@
   global $user;

   $comment = db_fetch_object(db_query('SELECT c.*, u.uid, u.name AS registered_name, u.data FROM {comments} c INNER JOIN {users} u ON c.uid = u.uid WHERE c.cid = %d', $cid));
+  if (!$comment) {
+    return drupal_not_found();
+  }
   $comment = drupal_unpack($comment);
   $comment->name = $comment->uid ? $comment->registered_name : $comment->name;
   if (comment_access('edit', $comment)) {