Class problem

1

hi
this is my class code

///
package
{
public class Rect
{
public var w:Number;
public var h:Number;
public function Rect(w:Number=0,h:Number=0)
{
this.w=w;
this.h=h ;
}
public function area():Number
{
return w * h / 2;

    }
}

}

and this is the code in my fla

///

import Rect;
var d:Rect=new Rect(10,20);

i am getting the error
5000: The class ‘RE.Rect’ must subclass ‘flash.display.MovieClip’ since it is linked to a library symbol of that type.

2 
package {
   import flash.display.MovieClip;
   public class Rect extends MovieClip {
      public var w:Number,h:Number;
      public function Rect(w:Number=0,h:Number=0) {
         this.w=w;
         this.h=h ;
      }
      public function area():Number {
         return w * h / 2;
      }
   }
}