Problem viewing flex in Safari

Question

I'm new to Flex and unable to view my Flex work in Safari...
Firefox works fine.
Here's one simple example:
http://www.papaya.net/test/flex/1/firstAnimation.html
You should see a red ball moving across the screen like this
screen cap from Firefox:
http://www.papaya.net/test/flex/1/firefox-snap.png
But in Safari I only get the grey background, no red ball. So
far none of my samples work in Safari.
Do you see the same problem?
These source files can be downloaded here:
http://www.papaya.net/test/flex/1/Archive.zip
My setup:
Mac Power Book G4
OSX 10.4.11
Safari 3.1.2
Flash player version 9,0,124,0 installed
Flex Builder 3

Answer 1

I changed the ball position as suggested, but still did not
work in Safari... still works in Firefox.
Here's that test:
http://www.papaya.net/test/flex/2/firstAnimation.html
I also checked with IE6/FlashPlayer9 and it works... what
version IE did not work?
The SWF plays ok in safari by itself, but not with the HTML
page code... we removed the javascript and it worked... don't know
if that's a real solution as the page code is being generated by
Flex Builder 3.
Here's the new AS code for the test linked above:
package {
import flash.display.Sprite;
import flash.events.Event;
public class firstAnimation extends Sprite {
private var ball:Sprite;
public function firstAnimation() {
init();
private function init():void {
ball = new Sprite();
addChild(ball);
ball.graphics.beginFill(0xff0000);
ball.graphics.drawCircle(0, 0, 40);
ball.graphics.endFill();
ball.x = 20;
ball.y = 50;
ball.addEventListener(Event.ENTER_FRAME, onEnterFrame);
private function onEnterFrame(event:Event):void {
ball.x++;