Dispatch event and external swf

1

I am loading an external swf into one class and in the external swf I am dispatching event like so:

dispatchEvent(new NavigationEvent(NavigationEvent.NAVIGATION_CHANGE, id));

now when i load this swf and cast is as object and try to add a listener:

 
private var _categoryNavigation:Object;
 
//when it loads
_categoryNavigation = _loader.content;
_categoryNavigation.addEventListener(NavigationEvent.NAVIGATION_CHANGE, categoryRangeChange);

i get a some weird error on runtime when it tries to dispatch an event:

 
TypeError: Error #1034: Type Coercion failed: cannot convert events::NavigationEvent@20a4e641 to events.NavigationEvent.
 at flash.events::EventDispatcher/flash.events:EventDispatcher::dispatchEventFunction()
 at flash.events::EventDispatcher/dispatchEvent()