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) {
		NAV_2009_01_over = newImage("images/NAV-2009_01-over.gif");
		NAV_2009_02_over = newImage("images/NAV-2009_02-over.gif");
		NAV_2009_03_over = newImage("images/NAV-2009_03-over.gif");
		NAV_2009_04_over = newImage("images/NAV-2009_04-over.gif");
		NAV_2009_05_over = newImage("images/NAV-2009_05-over.gif");
		NAV_2009_06_over = newImage("images/NAV-2009_06-over.gif");
		NAV_2009_07_over = newImage("images/NAV-2009_07-over.gif");
		NAV_2009_08_NAV_2009_01_over = newImage("images/NAV-2009_08-NAV-2009_01_ove.gif");
		NAV_2009_09_NAV_2009_01_over = newImage("images/NAV-2009_09-NAV-2009_01_ove.gif");
		preloadFlag = true;
	}
}