function newImage(arg) {
	if (document.images) {
		rslt = new Image();
		rslt.src = arg;
		return rslt;
	}
}

function changeImages() {
	if (document.images && (preloadFlag == true)) {
		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document[changeImages.arguments[i]].src = changeImages.arguments[i+1];
		}
	}
}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		roll_01_over = newImage("images/roll_01-over.gif");
		roll_01_roll_02_over = newImage("images/roll_01-roll_02_over.gif");
		roll_02_over = newImage("images/roll_02-over.gif");
		roll_03_roll_02_over = newImage("images/roll_03-roll_02_over.gif");
		roll_04_over = newImage("images/roll_04-over.gif");
		roll_04_roll_02_over = newImage("images/roll_04-roll_02_over.gif");
		roll_05_over = newImage("images/roll_05-over.gif");
		roll_05_roll_02_over = newImage("images/roll_05-roll_02_over.gif");
		roll_06_over = newImage("images/roll_06-over.gif");
		roll_07_over = newImage("images/roll_07-over.gif");
		roll_08_over = newImage("images/roll_08-over.gif");
		roll_10_over = newImage("images/roll_10-over.gif");
		roll_11_over = newImage("images/roll_11-over.gif");
		roll_12_over = newImage("images/roll_12-over.gif");
		preloadFlag = true;
	}
}