Smooth scrolling Help (actionscript easing)

After following the great tutorial on creating a Photo Gallery and then also following up with the Adding Thumbnails one. I’ve created a neat little portfolio type movie. Now I know a couple of people have asked about getting it to work with the Infinite Menu and scotty seemed to clear that up.

What I’m trying to achieve is getting the left and right scoll to ease out once you’ve scrolled to the last thumbnail on either side.

// Thumbnail Scroller actions.
function thumbNailScroller() {
    this.createEmptyMovieClip("tscroller", 1000);
    scroll_speed = 5;
    tscroller.onEnterFrame = function() {
        if ((_root._ymouse>=thumbnail_mc._y) && (_root._ymouse<=thumbnail_mc._y+thumbnail_mc._height)) {
            if ((_root._xmouse>=(hit_right._x-40)) && (thumbnail_mc.hitTest(hit_right))) {
                thumbnail_mc._x -= scroll_speed;
            } else if ((_root._xmouse<=40) && (thumbnail_mc.hitTest(hit_left))) {
                thumbnail_mc._x += scroll_speed;
        } else {
            delete tscroller.onEnterFrame;

I’m thinking I will need to add in some extra code into this block to get it working, but I’m stumped as to where?

Any help would be great…

Thanks in advance. =)