code: function(w) {
  			var t = this;
  
  			if (typeof(w) == 'string')
  				return w;
  
  			each(t.windows, function(wo) {
  				var ifr = DOM.get(wo.id + '_ifr');
  
  				if (ifr && w == ifr.contentWindow) {
  					w = wo.id;
  					return false;
  				}
  			});
  
  			return w;
  		}
docs: Internal functions