if (document.images) {            // Active Images

        img1on = new Image();
    img1on.src = "/images/nav_home_on.gif";
        img2on = new Image();
    img2on.src = "/images/nav_services_on.gif";
        img3on = new Image();
    img3on.src = "/images/nav_about_on.gif";
        img4on = new Image();
    img4on.src = "/images/nav_contact_on.gif";

        img1off = new Image();
    img1off.src = "/images/nav_home_on.gif";
    img2off = new Image();
    img2off.src = "/images/nav_services_off.gif";
        img3off = new Image();
    img3off.src = "/images/nav_about_off.gif";
        img4off = new Image();
    img4off.src = "/images/nav_contact_off.gif";
}


// Function to 'activate' images.
function imgOn(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "on.src");
        }
}

// Function to 'deactivate' images.
function imgOff(imgName) {
        if (document.images) {
            document[imgName].src = eval(imgName + "off.src");
        }
}