Need help adding args for an instance

Hey,

I am trying to add static arguments in a new instance, but for some reason dreamweaver is showing it as invalid. Any suggestions on what I am doing incorrectly?

class OrderConfirmation {

static public $apiversion = "2010-04-01";
static public $sid = "123";

public $confirmation_number = 1;
public $to_number = 3478870121;

public $client = new Services_Twilio(self::$sid); // This line is giving me an error?