var preloadFlag = false;

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];
		}
	}
}

function preloadImages() {
	if (document.images) {
		im1 = newImage("images/nav/business-over.gif");
		im2 = newImage("images/nav/corporate-over.gif");
		im3 = newImage("images/nav/financials-over.gif");
		im4 = newImage("images/nav/letter-over.gif");
		im5 = newImage("images/nav/patients-over.gif");
		im6 = newImage("images/nav/pipeline-over.gif");
		im7 = newImage("images/nav/products-over.gif");
		im8 = newImage("images/nav/strategy-over.gif");
		preloadFlag = true;
	}
}