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) {
		button_leasing_over = newImage("images/button_leasing_over.gif");
		button_construction_over = newImage("images/button_construction_over.gif");
		button_physical_over = newImage("images/button_physical_over.gif");
		button_accounting_over = newImage("images/button_accounting_over.gif");
		button_legal_over = newImage("images/button_legal_over.gif");
		button_it_over = newImage("images/button_it_over.gif");
		preloadFlag = true;
	}
}