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) {
		home_hover = newImage("images/home.gif");
		mail_hover = newImage("images/mail.gif");
		home_left_hover = newImage("images/home_left_hov.gif");
		company_hov = newImage("images/company_hov.gif");
		about_hov = newImage("images/about_hov.gif");
		contact_hov = newImage("images/contact_hov.gif");
		equipment_hov = newImage("images/equipment_hov.gif");
		employment_hov = newImage("images/employment_hov.gif");
		engineering_hov =  newImage("images/engineering_hov.gif");
		program_hov =  newImage("images/program_hov.gif");
		preloadFlag = true;
	}
}