if (document.images) {            // Active Images
            img1on = new Image();
            img1on.src = "images/menu1_on.gif";
            img1off = new Image();
            img1off.src = "images/menu1.gif";
            img2on = new Image();
            img2on.src = "images/menu2_on.gif";
            img2off = new Image();
            img2off.src = "images/menu2.gif";
            img3on = new Image();
            img3on.src = "images/menu3_on.gif";
            img3off = new Image();
            img3off.src = "images/menu3.gif";
            img4on = new Image();
            img4on.src = "images/menu4_on.gif";
            img4off = new Image();
            img4off.src = "images/menu4.gif";
            img5on = new Image();
            img5on.src = "images/menu5_on.gif";
            img5off = new Image();
            img5off.src = "images/menu5.gif";
            img6on = new Image();
            img6on.src = "images/menu6_on.gif";
            img6off = new Image();
            img6off.src = "images/menu6.gif";
            img7on = new Image();
            img7on.src = "images/menu7_on.gif";
            img7off = new Image();
            img7off.src = "images/menu7.gif";
            img8on = new Image();
            img8on.src = "images/menu8_on.gif";
            img8off = new Image();
            img8off.src = "images/menu8.gif";
            img9on = new Image();
            img9on.src = "images/menu9_on.gif";
            img9off = new Image();
            img9off.src = "images/menu9.gif";
            img10on = new Image();
            img10on.src = "images/menu10_on.gif";
            img10off = new Image();
            img10off.src = "images/menu10.gif";
            img11on = new Image();
            img11on.src = "images/menu11_on.gif";
            img11off = new Image();
            img11off.src = "images/menu11.gif";
            img12on = new Image();
            img12on.src = "images/menu12_on.gif";
            img12off = new Image();
            img12off.src = "images/menu12.gif";
            img13on = new Image();
            img13on.src = "images/menu13_on.gif";
            img13off = new Image();
            img13off.src = "images/menu13.gif";
            img14on = new Image();
            img14on.src = "images/forward_on.gif";
            img14off = new Image();
            img14off.src = "images/forward.gif";
            img15on = new Image();
            img15on.src = "images/menu15_on.gif";
            img15off = new Image();
            img15off.src = "images/menu15.gif";
            img16on = new Image();
            img16on.src = "images/menu16_on.gif";
            img16off = new Image();
            img16off.src = "images/menu16.gif";
            img17on = new Image();
            img17on.src = "images/menu17_on.gif";
            img17off = new Image();
            img17off.src = "images/menu17.gif";
            img18on = new Image();
            img18on.src = "images/menu18_on.gif";
            img18off = new Image();
            img18off.src = "images/menu18.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");
        }
}