Scrollbar

Hi guys,
I want to make a scrollbar and i have already this code (it’s stolen from Flash to the core) but this code is horizontal how can I make this scroll vertical?

Here’s the code:

// set up content_mc info
contentRight = _root.content_mc._x;
contentLeft = 715-_root.content_mc._width;

// set up gutter info
gutterLeft = _root.scrollbarGutter_mc._x+1;
gutterRight = ((_root.scrollbarGutter_mc._x+_root.scrollbarGutter_mc._width)-this._width)-1;

// don’t use the hand icon
this.useHandCursor = false;

// handle press event
this.onPress = function() {
this.startDrag(false, gutterLeft, this._y, gutterRight, this._y);
dragging = true;
this.onMouseMove = function() {
updateAfterEvent();
};
};

// handle release event
this.onRelease = this.onReleaseOutside = function() {
this.onMouseMove = undefined;
this.stopDrag();
dragging = false;
xSpeed = (newxpos-oldxpos)*RATIO;
};

// set initial variables
FRICTION = .9;
RATIO = .5;
dragging = false;

// handle onEnterFrame event
this.onEnterFrame = function() {
if (!dragging) {
oldxpos = this._x;
newxpos = oldxpos+xSpeed;
xSpeed = FRICTION;
if (newxpos>gutterRight || newxpos<gutterLeft) {
xSpeed = -FRICTION;
newxpos = oldxpos;
}
this._x = newxpos;
// always move content_mc whether dragging or not
var percent = (this._x-gutterLeft)/(gutterRight-gutterLeft);
this._parent.content_mc._x = percent
(contentLeft-contentRight)+contentRight;
} else {
oldxpos = newxpos;
newxpos = this._x;
// always move content_mc whether dragging or not
var percent = (this._x-gutterLeft)/(gutterRight-gutterLeft);
this._parent.content_mc._x = percent
(contentLeft-contentRight)+contentRight;
}
};