paymnet plugin

Hi,
I make a new payment plugin. Could you help me to check what I missed. After go to the payment, it returns successful. It went to the successful page but the payment status is NO and the Receipt # is nothing. Is it auotmatically update the status when the payment is completed?

Below is the part of my script:
class payment_paydollar extends payment {
function do_payment($payment_id, $member_id, $product_id,
$price, $begin_date, $expire_date, &$vars){

global $config;
global $db;
$products = $product_id;
$payment = $db->get_payment($payment_id);
$orig_product_id = $product_id;
if (is_array($product_id))
$product_id = $product_id[0];

$product = & get_product($product_id);
if (count($orig_product_id)>1)
$product->config['title'] = $config['multi_title'];

$u = & $db->get_user(intval($member_id));

$vars = array(
'merchantId' => $this->config['merchantid'],
'currCode' => $this->config['currcode'],
'payType' => $this->config['paytype'],
'cancelUrl' => $this->config['cancelurl'],
'failUrl' => $this->config['failurl'],
'successUrl' => $this->config['successurl'],
'amount' => sprintf('%.2f', $price),
'orderRef' => $payment_id,
'remark' => $member_id." | ".$product_id." | ".urlencode($product->config['title']),
'member_id' => $member_id,
'user_lv' => substr($u['data']['level_id'],3,1)
);
// add currency code
if (strlen($product->config['paypal_currency'])){
$vars['currency_code'] = $product->config['paypal_currency'];
};

$vars1 = array();
foreach ($vars as $kk=>$vv){
$v = urlencode($vv);
$k = urlencode($kk);
$vars1[] = "$kk=$vv";
}
$vars = join('&', $vars1);
header("Location: https://test.xxxxxxxx.com/b2cDemo/eng/payment/payForm.jsp?".$vars);
exit();
}
}

Thanks
KC

Payment Plugin

IT's A GREAT HELP!