codice:
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<title>Prova</title>
<script language="JavaScript" type="text/JavaScript">
<!--
function cange(opt){
if(opt==0){
var news = "qui nuovo valore x option 0"
document.form1.mainPage.options[0] = new Option(news)
}
if(opt==1){
var news = "qui nuovo valore x option 1"
document.form1.mainPage.options[1] = new Option(news)
}
}
//-->
</script>
</head>
<body>
<form name="form1" method="post" action="untitled-4.htm">
    

<select name="mainPage" style="width: 130px;" onchange="cange(this.value)">
	<option value="0">Interna</option>
<option value="1" selected="true">Principale</option>
</select></p>
</form>


</p>
</body>
</html>
Cosi puo andare?