var img;
var oldImgSrc;

if (document.images)
{
	img = new Array(2);
	
	img[0] = new Image();
	img[0].src = 'images/header/plan_trip_roll.gif';
	img[1] = new Image();
	img[1].src = 'images/header/contact_info_roll.jpg';
	img[2] = new Image();
	img[2].src = 'images/header/home_roll.gif';
	
}

function roll(index)
{
	oldImgSrc = document.images['foo' + index].src;
	document.images['foo' + index].src = img[index].src; 
}

function rolloff(index)
{
	document.images['foo' + index].src = oldImgSrc;
}