var base = "images/";
if (document.images) {
        img1on = new Image();   img1on.src = base + "prd_on.gif";
        img2on = new Image();   img2on.src = base + "abt_on.gif";
        img3on = new Image();   img3on.src = base + "mscience_on.gif";  
        img4on = new Image();   img4on.src = base + "prm_on.gif";
        img5on = new Image();   img5on.src = base + "mclub_on.gif";
        img6on = new Image();   img6on.src = base + "tsm_on.gif";
        img7on = new Image();   img7on.src = base + "cnd_on.gif";
        img8on = new Image();   img8on.src = base + "mcare_on.gif";

        // Inactive images
        img1off = new Image();   img1off.src = base + "prd_off.gif";
        img2off = new Image();   img2off.src = base + "abt_off.gif";
        img3off = new Image();   img3off.src = base + "mscience_off.gif";  
        img4off = new Image();   img4off.src = base + "prm_off.gif";
        img5off = new Image();   img5off.src = base + "mclub_off.gif";
        img6off = new Image();   img6off.src = base + "tsm_off.gif";
        img7off = new Image();   img7off.src = base + "cnd_off.gif";
        img8off = new Image();   img8off.src = base + "mcare_off.gif";
        }
        
        function imgOn(imgName) {
            if (document.images) {
                document[imgName].src = eval(imgName + "on.src");       
            }
    }

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