var scrollTimer = 0;
var scrollSpeed = 15;
function speedUp(value){
	scrollSpeed = value;
}
function slowDown(){
	scrollSpeed = 15;
}
function scrollDown(content){
	scrollTimer = setTimeout ("scrollDownDo('" + content + "')", scrollSpeed);
}
function scrollUp(content){
	scrollTimer = setTimeout ("scrollUpDo('" + content + "')", scrollSpeed);
}
function scrollDownDo(content){
	var elem = document.getElementById(content);
	if(elem.scrollTop < elem.scrollHeight){
		elem.scrollTop = elem.scrollTop + 2;
	}
	scrollTimer = setTimeout("scrollDownDo('" + content + "')", scrollSpeed);
}
function scrollUpDo(content){
	var elem = document.getElementById(content);
	if(elem.scrollTop > 0){
		elem.scrollTop = elem.scrollTop - 2;
	}
	scrollTimer = setTimeout("scrollUpDo('" + content + "')", scrollSpeed);
}
function scrollStop(){
	clearTimeout(scrollTimer);
}