Masking an image loader

programming flash
1

Hey guys, I’m coming from AS3 and I’m trying to mask a SWF file that’s being imported in but it’s doing something pretty funky. The SWF file is coming in fine, but when I’m masking it, it shows the shape I’m masking with, but it’s also masking because nothing is going beyond its’ edges.

Any ideas?
Thanks

{

var mask_mc:Shape = new Shape();
mask_mc.graphics.beginFill(0x000000);
mask_mc.graphics.drawRect(177, 0, 400, 300);
mask_mc.graphics.endFill();

addChild(mask_mc);


var imageRequest:URLRequest = new URLRequest("motion01.swf");
var imageLoader:Loader = new Loader();
var maskedImageLoader:MovieClip = new MovieClip();
imageLoader.load(imageRequest);
addChild(imageLoader);
mask_mc.mask = maskedImageLoader;
imageLoader.x = 177;
imageLoader.y = 0;

}