1) a.php?x=xxx&y=yyy, while submit form, action='redirect.php'; 2) redirect.php takes same para as a.php and header('xxx-yyy.htm'); 3) .htaccess with rule to url-rewrite a.php xxxx-yyy.htm a.php?x=xxx&y=yyy; now, my problem is, when a user submit a form inside a.php, redirect.php runs once, but a.php runs twice! how to fix this? thanks a lot.