function get_allow_payments($pay_service, $amount = 0)
{
    global $link;
    $result = array();
//get service params    
    $query = "  SELECT * 
                FROM payment_service_params
                WHERE psp_service = '$pay_service'";
    $res = mysql_query($query,$link);
    $service = mysql_fetch_object($res);
    //print_r($service);      
// get list of installed payment systems
    $payments = get_payments_list($pay_service);

    foreach ($payments as $payment) {

  $systems = get_allow_payments('premium',$amount);
//print_r($systems);    
	foreach ($systems as $ps){
	   $ps_list[] = $ps->ps_title;
    }
	return implode($ps_list, ', ');
}