drupal/error.php

<?php

include_once "includes/common.inc";

$errors = array(500 => "500 error: internal server error",
                404 => "404 error: `$REDIRECT_URL' not found",
                403 => "403 error: access denied - forbidden",
                401 => "401 error: authorization required",
                400 => "400 error: bad request");

watchdog("httpd", $errors[$REDIRECT_STATUS]);

if (strstr($REDIRECT_URL, "index.php")) {
  header("Location: ../index.php");
}
else {
  header("Location: index.php");
}

?>