Can not access navigationWindow from alloy.js

Hi, I am using titanium alloy for my project. I have some logic for opening and closing windows. For this logic i use small class which is written in alloy.js.

Alloy.Globals.nav = new Navigation();

my <NavigationWindow> element is in the index.xml where

Alloy.Globals.nav.setNaviWin($.naviWin)

the problem is that when i do

someWindow = Alloy.createController("login").getView();
Alloy.Globals.nav.openWindow(someWindow);

which is in alloy.js as:

funcition Navigation(){
........other code..........
        function setNaviWin(naviWin){
            this.naviWin = naviWin;
        }
........other code..........
    function openWindow(win){
              this.naviWin.openWindow(win);
        }
....other code.............
}

new window do not opens!?!?

But if i do this in index.js it works:

someWindow = Alloy.createController("login").getView();
$.naviWin.openWindow(someWindow);

Any ideas why it is not working with my navigation class in alloy.js? I debugged that this.naviWin in navigation object is properly assigned