proviamo così?

codice:
<html> 
<title>Documento senza titolo</title> 
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> 
<head> 

<script language="text/javascript"> 
<!--// 
var indirizzo = window.location.href; 
var to_frame="" 
var frame_direct=""
if (indirizzo == 'http://www.mysite.com/') { 
to_frame = "http://www.mysite.com/index_norm.php"; 
} 
else if (indirizzo == 'http://gest@mysite.com/') { 
to_frame= "http://www.mysite.com/gest/"; 
} 
else if (indirizzo == 'http://biella@mysite.com/') { 
to_frame= "http://www.mysite.com/biella/"; 
} 
else { 
to_frame= "http://www.mysite.com/idex_norm.php"; 
} 
frame_direct= "<FRAMESET ROWS=\"*,0\" FRAMEBORDER=\"0\" BORDER=\"0\" FRAMESPACING=\"0\"><frame src=\""+to_frame+"\" noresize></FRAMESET><noframes></noframes>"; 
document.write(frame_direct)
//--> 
</script> 
</head> 
<body> 
</body>