var scrollTimer;
var scrollContent, scrollArea, scrollBar, scrollBarUp, scrollBarDown;
var scrollSpeed = 4;
var scrollAcceleration = 20;

function scrollInit() {
	scrollContent = (document.getElementById) ? document.getElementById('scrollContent') : (document.all) ? document.all('scrollContent') : null;
	if (scrollContent) {
		scrollArea = (scrollContent.parentNode) ? scrollContent.parentNode : (scrollContent.parentElement) ? scrollContent.parentElement : null;
		scrollBar = (document.getElementById) ? document.getElementById('scrollBar') : (document.all) ? document.all('scrollBar') : null;
		scrollBarUp = (scrollBar.firstChild) ? scrollBar.firstChild : (scrollBar.all) ? scrollBar.all.tags('a')[0] : null;
		scrollBarDown = (scrollBar.lastChild) ? scrollBar.lastChild : (scrollBar.all) ? scrollBar.all.tags('a')[1] : null;
		scrollBarUp.onmouseover = new Function("scrollUp(scrollSpeed);");
		scrollBarUp.onmouseout = new Function("scrollStop();");
		scrollBarUp.onmousedown = new Function("scrollUp(scrollAcceleration);");
		scrollBarUp.onmouseup = new Function("scrollUp(scrollSpeed);");
		scrollBarDown.onmouseover = new Function("scrollDown(scrollSpeed);");
		scrollBarDown.onmouseout = new Function("scrollStop();");
		scrollBarDown.onmousedown = new Function("scrollDown(scrollAcceleration);");
		scrollBarDown.onmouseup = new Function("scrollDown(scrollSpeed);");
		scrollContent.style.top = 0;
		if (scrollContent.offsetHeight > scrollArea.offsetHeight) scrollBar.style.visibility = 'visible';
	};
};

function scrollUp(step) {
	scrollStop();
	scrollTimer = window.setInterval("scrollContent.style.top = (parseInt(scrollContent.style.top) + " + step + " < 0) ? parseInt(scrollContent.style.top) + " + step + " + 'px' : '0px';", 50);
};

function scrollDown(step) {
	scrollStop();
	scrollTimer = window.setInterval("scrollContent.style.top = (parseInt(scrollContent.style.top) - " + step + " > scrollArea.offsetHeight - scrollContent.offsetHeight) ? parseInt(scrollContent.style.top) - " + step + " + 'px' : scrollArea.offsetHeight - scrollContent.offsetHeight + 'px';", 50);
};

function scrollStop() {
	if (scrollTimer) window.clearInterval(scrollTimer);
};