var timer;

function initialize ()
{
	document.getElementById('menu_movable').style.left = '0px';

	document.getElementById('left_arrow').onmouseover = function ()
	{
		timer = setInterval("moveleft()", 20);
	}

	document.getElementById('left_arrow').onmouseout = function ()
	{
		clearInterval(timer);
	}

	document.getElementById('right_arrow').onmouseover = function ()
	{
		timer = setInterval("moveright()", 20);
	}

	document.getElementById('right_arrow').onmouseout = function ()
	{
		clearInterval(timer);
	}
}

function moveleft()
{
	var movableDiv = document.getElementById('menu_movable');
	var X = parseInt(movableDiv.style.left);
	movableDiv.style.left = X <= -510 ? X+"px" : (X-2)+"px";
}

function moveright()
{
	var movableDiv = document.getElementById('menu_movable');
	var X = parseInt(movableDiv.style.left);
	movableDiv.style.left = X >= 0 ? X+"px" : (X+2)+"px";
}