[loover]

спасибо, приведение типов сработало. но теперь ругается на tabChildren:

private var roots:DisplayObject;
private var rootss:InteractiveObject;
...
rootss = roots as InteractiveObject;
...
rootss.tabEnabled = false;
rootss.tabChildren = false;
...
1119: Access of possibly undefined property tabChildren through a reference with static type flash.display:InteractiveObject.