AS3 Pan and Zoom Thumbs

I’m building a thumbnail display that scrolls with the mouse movement and when you rollover an image it will zoom in on it (scale). I’ve got the scroll working but can’t seem to get the zoom to take effect.

I have two mc’s. Panel which contains all the images, and stroke which helps with the scroll action. I’m using AS3, and here is my code:

panel.onRollOver = panelOver;

function panelOver() {
    this.onEnterFrame = scrollPanel;
    delete this.onRollOver;

var b = stroke.getBounds(_root);

function scrollPanel() {
    if(_xmouse<b.xMin || _xmouse>b.xMax || _ymouse<b.yMin || _ymouse>b.yMax) {
        this.onRollOver = panelOver;
        delete this.onEnterFrame;
    if(panel._x >= 1500) {
        panel._x = 1500;
    if(panel._x <= -751) {
        panel._x = -751;
    var xdist = _xmouse - 350;
    panel._x += Math.round(-xdist / 7);

I’ve taken out what code I had for the scale affect as it didn’t work at all… I’m a little out of ideas; this is my first attempt with AS3. I know that I need to do a scale, and that’s about as far as I can get. I’m going to keep scouring the net for ideas, but also wondering if anyone here as the time and interest to lend a hand. I’m trying to recreate something similar to the mac toolbar.