linux下类无法实例化.该怎么处理

ini_set ( "error_reporting", "E_ALL & ~E_NOTICE" );
include '../bld_controller/LoginHandle.class.php';
$username = $_POST['username'];
$password = $_POST['password'];
$login = new LoginHandle();//运行到这一步就停止了
$flag = $login->check_psw($username, $password);
if($flag)
{
	session_start();
	$_SESSION['username'] = $username;
	echo "";
}
else
{
	echo "";
}




?>

class LoginHandle
{
	var $db = "";
	var $flag ="";
	function __construct()
	{
		$this->db = new DBhelper("yaoinger", "123456", "108.163.234.83:2082", "banklinksdisbution");
		$this->flag = $this->db->connect();
			
	}
	function check_psw($username,$password)
	{
		$SQL = "SELECT u_password FROM bld_users WHERE u_name ='$username'";
		$result ="";
		if($this->flag)
		{
			$result = $this->db->select($SQL);
		}
		$psw = "";
		if($result){
		$value= mysql_fetch_assoc($result);
		}
		$psw = $value['u_password'];
		return $psw == $password;
		
	}
	
	
}