Unity crash when i use MasterServer.RegisterHost script

Now i learning how to make multiplayer game and i have problem when i use “MasterServer.RegisterHost(gameName, name, des)” Unity crash. Code (read comments):

#pragma strict
var gameName : String = "Kmcdiklomnd_Learning_Multiplayer";

private var btnX : float;
private var btnY : float;
private var btnW : float;
private var btnH : float;

function Start(){
	btnX = Screen.width * 0.05;
	btnY = Screen.width * 0.05;
	btnW = Screen.width * 0.1;
	btnH = Screen.width * 0.1;

function startServer(){
	Network.InitializeServer(4, 25001, !Network.HavePublicAddress);
    // I use yield WaitForSeconds(2); to test then Unity crash.
	yield WaitForSeconds(2);
    // If i delete this \/ line of code everything works, so this line crash Unity
	MasterServer.RegisterHost(gameName, "Learning Multiplayer Game Name", "This is learning game");

function OnServerInitialized(){
	Debug.Log("Server initialized!");

// This function dont work because Unity crash before it start
function OnMasterServerEvent(mse : MasterServerEvent){
	if(mse == MasterServerEvent.RegistrationSucceeded){
		Debug.Log("Registered Server!");

function OnGUI () {
	if(GUI.Button(Rect(btnX, btnY, btnW, btnH), "Start Server")){
		Debug.Log("Starting Server");
	if(GUI.Button(Rect(btnX, btnY * 1.2 + btnH, btnW, btnH), "Refresh Host")){

So did anyone know how to fix it?

Cutting and pasting your exact code into a Unity project here (4.3.4) works exactly as expected.