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

function changeImages() {

		for (var i=0; i<changeImages.arguments.length; i+=2) {
			document.getElementById(changeImages.arguments[i]).src = changeImages.arguments[i+1];
		}

}

var preloadFlag = false;
function preloadImages() {
	if (document.images) {
		header_02_over = newImage("images/header/header_02-over.gif");
		header_03_over = newImage("images/header/header_03-over.gif");
		header_04_over = newImage("images/header/header_04-over.gif");
		header_05_over = newImage("images/header/header_05-over.gif");
		preloadFlag = true;
	}
}