Index: modules/user/user.module
===================================================================
RCS file: /cvs/drupal/drupal/modules/user/user.module,v
retrieving revision 1.745
diff -u -p -r1.745 user.module
--- modules/user/user.module	11 Jan 2007 08:52:45 -0000	1.745
+++ modules/user/user.module	14 Jan 2007 03:32:14 -0000
@@ -794,7 +794,7 @@ function user_menu($may_cache) {
     if (arg(0) == 'user' && is_numeric(arg(1)) && arg(1) > 0) {
       $account = user_load(array('uid' => arg(1)));
 
-      if ($user !== FALSE) {
+      if ($account !== FALSE) {
         // Always let a user view their own account
         $view_access |= $user->uid == arg(1);
         // Only admins can view blocked accounts
@@ -827,6 +827,10 @@ function user_menu($may_cache) {
           }
         }
       }
+      else {
+        $items[] = array('path' => 'user/'. arg(1), 'type' => MENU_CALLBACK, 
+          'callback' => 'drupal_not_found', 'access' => $view_access);
+      }
     }
   }