ce l'ho fatta anche prima di pranzo....ho perfezionato qualcosina.....
adattatelo tu alla pagina:
codice:
<html>
<head>

<script language="Javascript">
function recupera(name_ID) { 
	return (document.all)?document.all[name_ID]:(document.getElementById)?document.getElementById(name_ID):null 
}
function add_campo(rec){
if (recupera('campi').innerHTML==''){
for(i=0;i<(rec-1);i++){
recupera('campi').innerHTML+="<input type='text' id='persona"+(i+1)+"'>
";
}
}
else{
recupera('campi').innerHTML=" ";
for(i=0;i<(rec-1);i++){
recupera('campi').innerHTML+="<input type='text' id='persona"+(i+1)+"'>
";
}
}
}
</script>
</head>
<body>
<form>
<select name="numero_persone" onChange="add_campo(this[this.selectedIndex].value)">
<option value="1">1</option>
<option value="2">2</option>
<option value="3">3</option>
<option value="4">4</option>
<option value="5">5</option>
</select> 
<div id="campi"></div>
<input type="submit">
</form>
</body>
</html>