interesting use of declaring a function inside a tween like that
didnt know you could do such a thing..
i have always used it like that (for examle onComplete in TweenMax)
var myT:TimelineLite = new TimelineLite();
myT.insert(new TweenLite(mcBall,1,{scaleX:1,scaleY:1,onStart:myfunction}),0);
// and then write this function out separately
function myfunction(){
mcBall.scaleX = 10;mcBall.scaleY = 10
}
not sure if it works or not in your case because I haven't used Timeline classes before
Cheers,
Martin