function popupWindow(arg) {
        window.open("popup.html","popup","location=no,scroll=yes,scrollbars=no,resizable=no,height=434,width=458"); 
}

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_home_over = newImage("images/nav_home_over.gif");
                nav_approach_over = newImage("images/nav_approach_over.gif");
                nav_founder_over = newImage("images/nav_founder_over.gif");
                nav_services_over = newImage("images/nav_services_over.gif");
                nav_clients_over = newImage("images/nav_clients_over.gif");
                nav_contact_over = newImage("images/nav_contact_over.gif");
                preloadFlag = true;
        }
}