attachMovie with as3

Hi,

Can someone write a simple class that attach Movie clip on stage, and dont extends MovieClip…

something like as2:

class Movie {

   private var mc:MovieClip


  public function Movie(){
   init()
  }
  public function init(){
   var _container = this.createEmptyMovieClip("container",1)
   mc:MovieClip = _container.attachMovie("abc","abc",1)
 }
}

i always have something like 5000: The class ‘First’ must subclass ‘flash.display.MovieClip’ since it is linked to a library symbol of that type.