jquery invio dati post

[Phone]

salve ho questo script che mi prende le info dal form e me le manda a un altro file che me le elabora.

il problema e che sul database mi scrive undefinite.....nonostante il value è pieno
forse con i codici è piu' chiaro


index.php

 <script type="text/javascript" src="../../../programmi/imagezoom/jquery-latest.js"></script>

<script type="text/javascript" src="invio.js"></script>



 <form>
 <fieldset>
  <legend>Valutazione</legend>
Bellezza

1<input type="radio" name="bellezza" value="1" Change="valida();" />
2<input type="radio" name="bellezza" onChange="valida();" value="2"/>
3<input type="radio" name="bellezza" onChange="valida();" value="3"/>
4<input type="radio" name="bellezza" onChange="valida();" value="4"/>
5<input type="radio" name="bellezza" onChange="valida();" value="5"/>
6<input type="radio" name="bellezza" onChange="valida();" value="6"/>
7<input type="radio" name="bellezza" onChange="valida();" value="7"/>
8<input type="radio" name="bellezza" onChange="valida();" value="8"/>
9<input type="radio" name="bellezza" onChange="valida();" value="9"/>
10<input type="radio" name="bellezza" onChange="valida();" value="10"/>

<div id="message">
</div>

</fieldset>

</form> 

invio.js

 // JavaScript Document
function valida() {
	var oXHR = new XMLHttpRequest();
	oXHR.open("post","invio.php",true);
	oXHR.setRequestHeader("Content-Type","application/x-www-form-urlencoded");
	oXHR.onreadystatechange = function(){
		
			if(oXHR.readyState == 4){
			var message = document.getElementById("message");
            if(oXHR.responseText =='OK'){
				
				message.innerHTML = "<p style=\"color:red\">Email gi&agrave; usata</p>";
				}else{
					message.innerHTML ="";
					}
					
					
					
		}
	}


	var params ="bellezza=" + encodeURIComponent(document.forms[0].bellezza.value);
	
	oXHR.send(params);
}

invio.php

<?php require_once('../../../Connections/connessione.php'); ?>
<?php
if (!function_exists("GetSQLValueString")) {
function GetSQLValueString($theValue, $theType, $theDefinedValue = "", $theNotDefinedValue = "") 
{
  if (PHP_VERSION < 6) {
    $theValue = get_magic_quotes_gpc() ? stripslashes($theValue) : $theValue;
  }

  $theValue = function_exists("mysql_real_escape_string") ? mysql_real_escape_string($theValue) : mysql_escape_string($theValue);

  switch ($theType) {
    case "text":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;    
    case "long":
    case "int":
      $theValue = ($theValue != "") ? intval($theValue) : "NULL";
      break;
    case "double":
      $theValue = ($theValue != "") ? doubleval($theValue) : "NULL";
      break;
    case "date":
      $theValue = ($theValue != "") ? "'" . $theValue . "'" : "NULL";
      break;
    case "defined":
      $theValue = ($theValue != "") ? $theDefinedValue : $theNotDefinedValue;
      break;
  }
  return $theValue;
}
}




$trovato = false;



 $insertSQL = sprintf("INSERT INTO prova (bellezza) VALUES ( %s)",

                       GetSQLValueString($_POST['bellezza'], "text"));

  mysql_select_db($database_connessione, $connessione);
  $Result1 = mysql_query($insertSQL, $connessione) or die(mysql_error());

$trovato = true;




if($trovato){
    
    echo 'OK';
    
}else{

echo 'KO';
}

?>

a scrivere sul database scrive.....solo mi scrive undefinite