var speed=5
var moveupvar; 
var crossobj=document.getElementById? document.getElementById("scroll-content") : document.all.content
var contentheight=crossobj.offsetHeight

function movedown(){
if (parseInt(crossobj.style.top)>=(contentheight*(-1)+100))
	crossobj.style.top=parseInt(crossobj.style.top)-speed+"px"
	movedownvar=setTimeout("movedown()",20)
}

function moveup(){
	if (parseInt(crossobj.style.top)<=0)
		crossobj.style.top=parseInt(crossobj.style.top)+speed+"px"
	moveupvar=setTimeout("moveup()",20)
}

function getcontent_height(){
	contentheight=crossobj.offsetHeight
}
function moveTop(){
	crossobj.style.top="0px"
}
function moveBottom(){
	crossobj.style.top=parseInt(contentheight*(-1)+100)+"px"
}
getcontent_height;