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 preloadMapImages() {
	if (document.images) {
		qld_over = newImage("images/qld-over.jpg");
		qld_sa_over = newImage("images/qld-sa_over.jpg");
		nt_over = newImage("images/nt-over.jpg");
		wa_over = newImage("images/wa-over.jpg");
		sa_over = newImage("images/sa-over.jpg");
		sa_over020 = newImage("images/sa-over-20.jpg");
		nsw_over = newImage("images/nsw-over.jpg");
		vic_over = newImage("images/vic-over.jpg");
		vic_nsw_over = newImage("images/vic-nsw_over.jpg");
		nsw_over030 = newImage("images/nsw-over-30.jpg");
		tas_over = newImage("images/tas-over.jpg");
		preloadFlag = true;
	}
}