paypal et ipn

Bonjour,

je suis sur se problème et je ne trouve pas de solution depuis des heures .

Warning: fsockopen() [function.fsockopen]: unable to connect to ssl://www.sandbox.paypal.com:443 (Unable to find the socket transport "ssl" - did you forget to enable it when you configured PHP?) in C:\wamp\www\webroot\ipn.php on line 14

voici mon code :

<?php
//permet de traiter le retour ipn de paypal
$email_account = "sell_1328887673_biz@live.fr";
$req = 'cmd=_notify-validate';
foreach ($_POST as $key => $value) {
    $value = urlencode(stripslashes($value));
    $req .= "&$key=$value";
}
$header = "POST /cgi-bin/webscr HTTP/1.0\r\n";
$header .= "Content-Type: application/x-www-form-urlencoded\r\n";
$header .= "Content-Length: " . strlen($req) . "\r\n\r\n";
$fp = fsockopen ('ssl://www.sandbox.paypal.com', 443, $errno, $errstr, 30);
$item_name = $_POST'item_name'];
$item_number = $_POST'item_number'];
$payment_status = $_POST'payment_status'];
$payment_amount = $_POST'mc_gross'];
$payment_currency = $_POST'mc_currency'];
$txn_id = $_POST'txn_id'];
$receiver_email = $_POST'receiver_email'];
$payer_email = $_POST'payer_email'];
parse_str($_POST'custom'],$custom);
if (!$fp) 
{
} 
else 
{
    fputs ($fp, $header . $req);
    while (!feof($fp)) 
    {
        $res = fgets ($fp, 1024);
        if (strcmp ($res, "VERIFIED") == 0) 
        {
            // vérifier que payment_status a la valeur Completed
            if ( $payment_status == "Completed") 
            {
               if ( $email_account == $receiver_email) 
                {
                    /**
                    * C'EST LA QUE TOUT SE PASSE
                    * PS : tjrs penser à vérifier la somme !!
                    */  
                    file_put_contents('log', print_r($_POST,true));
                    require "config.php";
                    mysql_connect(DB_SERVER,DB_LOGIN,DB_PASS);
                    mysql_select_db(DB_NAME);
                    mysql_query('SET NAMES'.DB_ENC);
                    $req = mysql_query('SELECT * FROM offres WHERE prix='.$payment_amount.' LIMIT 1');
                    $d = mysql_fetch_assoc($req) ;

                    if (!empty($d)) 
                    {
                        $duration = $d'durer'];
                        $uid = $custom'uid'];
                        $datas = serialize($_POST);
                        mysql_query('UPDATE users set expiration = DATE_ADD(NOW(), INTERVAL '.$duration.' MONTH) WHERE id='.$uid);
                        mysql_query("INSERT INTO factures set user_id='$uid', amount='$payment_amount', created=NOW(), datas='$datas' ");
                        file_put_contents('log','Le paiment a bien été confirmé ');
                    }
                    else
                    {
                        file_put_contents('log','Le paiment ne correspond à aucune offre');
                    }
                }
            }
            else 
            {

            }
            exit();
        }
        else if (strcmp ($res, "INVALID") == 0) 
        {

        }
    }
    fclose ($fp);
} 
?>

et ma page d erreur :

( ! ) Warning: fsockopen() [function.fsockopen]: unable to connect to ssl://www.sandbox.paypal.com:443 (Unable to find the socket transport "ssl" - did you forget to enable it when you configured PHP?) in C:\wamp\www\webroot\ipn.php on line 14
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
2   0.0006  704176  fsockopen ( )   ..\ipn.php:14
( ! ) Notice: Undefined index: item_name in C:\wamp\www\webroot\ipn.php on line 15
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: item_number in C:\wamp\www\webroot\ipn.php on line 16
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: payment_status in C:\wamp\www\webroot\ipn.php on line 17
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: mc_gross in C:\wamp\www\webroot\ipn.php on line 18
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: mc_currency in C:\wamp\www\webroot\ipn.php on line 19
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: txn_id in C:\wamp\www\webroot\ipn.php on line 20
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: receiver_email in C:\wamp\www\webroot\ipn.php on line 21
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: payer_email in C:\wamp\www\webroot\ipn.php on line 22
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0
( ! ) Notice: Undefined index: custom in C:\wamp\www\webroot\ipn.php on line 23
Call Stack
#   Time    Memory  Function    Location
1   0.0005  703040  {main}( )   ..\ipn.php:0