Can't get Scrollbar to resize to movieclip content

Hi,

I have been using AS (for student projects) for a little over a year now, and am currently hung up on a basic problem with the scrollpane component which I am not too familiar with. I’ve read all the documentation, and searched around a lot online, but can’t get the scrollbar’s size to respond to the content of the scrollpane. Any help would be greatly appreciated.

Here is my code:

var i = 1; //index for URL entries
var URLY = 0;
var URL_num = 1;
var URL_list;

URL_pane.onLoad = function() {

this.contentPath = "URLPaneBG";  //holder mc linkage name
URL_list = this.content;

}

addURL_btn.onRelease = function() {

URL_list.attachMovie("URLEntry", "URLEntry"+i, i);
URL_list["URLEntry"+i]._x = 0;
URL_list["URLEntry"+i]._y = URLY;
URL_list["URLEntry"+i].URL_num.text = URL_num;
	
i++;
URLY += 28;
URL_num++;

}

Ian