You may use die() or the equivalent exit() after a redirection ( via the header statement )
<code>
header("location : http://www.differentpage.com");
die();
<code>
this may seem strange but you have to rememeber that header affects the client not the server script ( in fact it will continue to be executed if you dont stop it)
of course you can let the script continue but someone forget this behaviour and get "strange errors"