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];
            }
        }
				return true;
    }

    var preloadFlag = false;
    function preloadImages() {
        if (document.images) {
            partners         = newImage("./images/a_partners.gif");
            about        = newImage("./images/a_about.gif");
            training        = newImage("./images/a_training.gif");
            fhwa     = newImage("./images/a_fhwa.gif");
            reference    = newImage("./images/a_reference.gif");
            links        = newImage("./images/a_links.gif");
            preloadFlag     = true;
        }
				
    }