Scalable Dynamic JPEG on Full Browser Flash Site

Ok … I’m going out of my head here. I’ve found a lot of posts in the forums here that have come oh so close to answering my question but just not quite.

I’ve got a full browser flash movie I’m creating. I’ve got a movie that scales out to 100% x 100% which has a dynamically loading JPEG for a background image and another empty movie clip that loads in the main content.

Here’s my ActionScript:

stop();

loadMovie("dh_main.swf","mainContent_mc");
loadMovie("background.jpg","background");

Stage.scaleMode = "noscale";

stageListener.onResize = function () {
    var stageXCenter = Stage.width * .5;
    var stageYCenter = Stage.height * .5;
}

I want the background image to scale 100% x 100% and resize with the mainContent_mc when the window is resized.

I just cannot get that background JPEG to stretch to save my life.

Any ideas?