Quite a basic question

Hi, This is quite a very basic question, but i think the code following my signature should work. Instead, i get a "Warning: Cannot modify header information - headers already sent by (output started at /home/vhosts/dte/cv/register_action.php:10) in /home/vhosts/dte/cv/register_action.php on line 12" and no redirection :( How can i solve this ? Any help would be apreciated. Warm Regards, Mário Gamito <?php $hostname = gethostbyaddr($_SERVER['REMOTE_ADDR']); $sub_domain = explode (".", $hostname); if ($sub_domain[1] != 'dte') {

    echo"
    <script language=\"JavaScript\">
	  window.open (\"http://www.google.com\", \"mywindow\", \"status=1, toolbar=0, resizable=0,

width=200, height=200\");

    </script>";	

} header("Location: http://www.dte.ua.pt/cv/"); ?> <HTML> <HEAD> <TITLE>Gestão de currículos do DDTE</TITLE> (...)