if (document.images) {

// Static gif..
    img1off = new Image();
    img1off.src = "../images/nav01.gif";
    img2off = new Image();
    img2off.src = "../images/nav02.gif";
    img3off = new Image();
    img3off.src = "../images/nav03.gif";
    img4off = new Image();
    img4off.src = "../images/nav04.gif";
    img5off = new Image();
    img5off.src = "../images/nav05.gif";
    img6off = new Image();
    img6off.src = "../images/nav06.gif";
    img7off = new Image();
    img7off.src = "../images/nav07.gif";

    img10off = new Image();
    img10off.src = "../images/sub_marine.gif";
    img11off = new Image();
    img11off.src = "../images/sub_lifestyle.gif";
    img12off = new Image();
    img12off.src = "../images/sub_industrial.gif";
    img13off = new Image();
    img13off.src = "../images/sub_rugged.gif";


// Mouseover gif..
    img1on = new Image();
    img1on.src = "../images/nav01r.gif";
    img2on = new Image();
    img2on.src = "../images/nav02r.gif";
    img3on = new Image();
    img3on.src = "../images/nav03r.gif";
    img4on = new Image();
    img4on.src = "../images/nav04r.gif";
    img5on = new Image();
    img5on.src = "../images/nav05r.gif";
    img6on = new Image();
    img6on.src = "../images/nav06r.gif";
    img7on = new Image();
    img7on.src = "../images/nav07r.gif";

    img10on = new Image();
    img10on.src = "../images/sub_mariner.gif";
    img11on = new Image();
    img11on.src = "../images/sub_lifestyler.gif";
    img12on = new Image();
    img12on.src = "../images/sub_industrialr.gif";
    img13on = new Image();
    img13on.src = "../images/sub_ruggedr.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");
        }
}