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.el.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(){
	document.getElementById('scroll').style.height=document.getElementById('textfield').offsetHeight-"15";
	objContainer=new ConstructObject('scroll')
	objScroller=new ConstructObject('scrollContent','scroll')
	objScroller.MoveArea(0,0)
	objContainer.css.visibility='visible'
	initialised=true;
}