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_over                   = newImage("/images/home_over.gif");
        sign_in_over                = newImage("/images/sign_in_over.gif");
        demo_over                   = newImage("/images/demo_over.gif");
        invite_over                 = newImage("/images/invite_over.gif");
        bulb_on                     = newImage("/images/bulb_on.gif");
        about_us_over               = newImage("/images/about_us_over.gif");
        products_over               = newImage("/images/products_over.gif");
        accessibility_left_nav_over = newImage("/images/accessibility_left_nav_over.gif");
        services_left_nav_over      = newImage("/images/services_left_nav_over.gif");
        support_left_nav_over       = newImage("/images/support_left_nav_over.gif");
        training_left_nav_over      = newImage("/images/training_left_nav_over.gif");
        partners_left_nav_over      = newImage("/images/partners_left_nav_over.gif");
        request_info_left_nav_over  = newImage("/images/request_info_left_nav_over.gif");
        buy_now_left_nav_over       = newImage("/images/buy_now_left_nav_over.gif");
        community_left_nav_over     = newImage("/images/community_left_nav_over.gif");
        preloadFlag = true;
    }
}