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) {
		index_30_over = newImage("zdj/index_30-over.jpg");
		index_37_over = newImage("zdj/index_37-over.jpg");
		index_44_over = newImage("zdj/index_44-over.jpg");
		index_51_over = newImage("zdj/index_51-over.jpg");
		index_58_over = newImage("zdj/index_58-over.jpg");
		preloadFlag = true;
	}
}