Shared Library question in AS3/CS3...

Hm...  I don't seem to be able to get this Shared Library in AS3/CS3...  :(

I have SharedLibrary.fla file where I have a movieClip linked as Square for the class, flash.display.MovieClip, and Export for ActionScript and Export in first frame are checked...

I have SharedLibraryMain.fla file where I have the following script...

var loader:Loader = new Loader();
var request:URLRequest = new URLRequest("SharedLibrary.swf");
loader.contentLoaderInfo.addEventListener('complete', completeHandler);
loader.load(request);

function completeHandler(e):void
{
      var square:Class = getDefinitionByName("Square") as Class;
      addChild(square);
}

But that gives me this '1067: Implicit coercion of a value of type Class to an unrelated type flash.display:DisplayObject.' error message...  I can use that method to use the image or font just fine, but I am not able to use a movieClip...  What am I missing here???

Thanks...  :)