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) {
		nav_people_over = newImage("images/nav-people-over.gif");
		nav_background_over = newImage("images/nav-background-over.gif");
		nav_criminal_over = newImage("images/nav-criminal-over.gif");
		nav_employment_over = newImage("images/nav-employment-over.gif");
		nav_allproduct_over = newImage("images/nav-allproduct-over.gif");
		btn_search1_over = newImage("images/btn-search1-over.png");
		btn_search2_over = newImage("images/btn-search2-over.gif");
		preloadFlag = true;
	}
}