Proba con el siguiente codigo creo que es lo que necesitas lo extraje de la pagina que dejaste
<html>
<head>
<title></title>
<script language="JavaScript">
function verifyCompatibleBrowser(){
this.ver=navigator.appVersion
this.dom=document.getElementById?1:0
this.ie5=(this.ver.indexOf("MSIE 5")>-1 && this.dom)?1:0;
this.ie4=(document.all && !this.dom)?1:0;
this.ns5=(this.dom && parseInt(this.ver) >= 5) ?1:0;
this.ns4=(document.layers && !this.dom)?1:0;
this.bw=(this.ie5 || this.ie4 || this.ns4 || this.ns5)
return this
}
bw=new verifyCompatibleBrowser()
var speed=50
var loop, timer
function ConstructObject(obj,nest){
nest=(!nest) ? '':'document.'+nest+'.'
this.el=bw.dom?document.getElementById(obj):bw.ie4 ?document.all[obj]:bw.ns4?eval(nest+'document.'+obj):0;
this.css=bw.dom?document.getElementById(obj).style :bw.ie4?document.all[obj].style:bw.ns4?eval(nest+'document.'+obj):0;
this.scrollHeight=bw.ns4?this.css.document.height: this.el.offsetHeight
this.clipHeight=bw.ns4?this.css.clip.height:this.e l.offsetHeight
this.up=MoveAreaUp;this.down=MoveAreaDown;
this.MoveArea=MoveArea; this.x; this.y;
this.obj = obj + "Object"
eval(this.obj + "=this")
return this
}
function MoveArea(x,y){
this.x=x;this.y=y
this.css.left=this.x
this.css.top=this.y
}
function MoveAreaDown(move){
if(this.y>-this.scrollHeight+objContainer.clipHeight){
this.MoveArea(0,this.y-move)
if(loop) setTimeout(this.obj+".down("+move+")",speed)
}
}
function MoveAreaUp(move){
if(this.y<0){
this.MoveArea(0,this.y-move)
if(loop) setTimeout(this.obj+".up("+move+")",speed)
}
}
function PerformScroll(speed){
if(initialised){
loop=true;
if(speed>0) objScroller.down(speed)
else objScroller.up(speed)
}
}
function CeaseScroll(){
loop=false
if(timer) clearTimeout(timer)
}
var initialised;
function InitialiseScrollableArea(){
objContainer=new ConstructObject('divContainer')
objScroller=new ConstructObject('divContent','divContainer')
objScroller.MoveArea(0,0)
objContainer.css.visibility='visible'
initialised=true;
}
</script>
</head>
<body onload="InitialiseScrollableArea()">
<p align="left"><a href="javascript
:;" onMouseOver="PerformScroll(-2)" onMouseOut="CeaseScroll()"><img border="0" src="arriba_on.jpg" width="14" height="14"></a></p>
<p align="left"><a href="javascript
:;" onMouseOver="PerformScroll(2)" onMouseOut="CeaseScroll()"><img border="0" src="abajo_on.jpg" width="14" height="14"></a></p>
<div style="position: absolute; width: 178px; height: 51px; z-index: 0; left: 30px; top: 14px; clip:rect(0,178,51,0); overflow:visible; visibility: visible" id="divContainer">
<div style="position: absolute; visibility: visible; left: 0px; top: 0px" id="divContent">
<p>xxxx</p>
<p>xxxx</p>
<p>xxxx</p>
<p>xxxx</p>
<p>xxxx</p>
</div>
</div>
</body>
</html>