Class doesn't work for me

Hi,

I try you class and when i try to send a smtp mail with i receive this error :

Fatal error: Default value for parameters with a class type hint can only be NULL in /public_html/class/Mail.class.php on line 204


//Example using smtp
$mail = new Mail;

//Set subject and sender of the mail.
$mail->setSubject('Example mail');
$mail->setSender('test@domain.com');
//Set the plain content of the mail.
$mail->setContentPlain('Example plain-content!');
//Add a receiver of the mail (you can add more than one receiver too).
$mail->addReceiver('test1@domain.com');

$mail->isSMTP(true,array('host'=>"mail.domain.ca",
'user'=>'user@domain.com',
'pass'=>'pwd',
'port'=>465));
//Finally send the mail.
var_dump($mail->send());

Do you have any solution for me?

Thanks

Which version of php you were used?