if (document.images) {            // Active Images
            img1on = new Image();
            img1on.src="http://www.impactfactory.com/images/nav/home-ovr.gif"; 
            img2on = new Image(); 
            img2on.src="http://www.impactfactory.com/images/nav/about-ovr.gif";  
            img3on = new Image();
            img3on.src="http://www.impactfactory.com/images/nav/prog-ovr-at.gif";
            img4on = new Image();
            img4on.src="http://www.impactfactory.com/images/nav/library-ovr.gif";
            img5on = new Image();
            img5on.src="http://www.impactfactory.com/images/nav/new-ovr.gif";
            img6on = new Image();
            img6on.src="http://www.impactfactory.com/images/nav/more-ovr.gif";

            img1off = new Image(); 
            img1off.src="http://www.impactfactory.com/images/nav/home.gif"; 
            img2off = new Image();
            img2off.src="http://www.impactfactory.com/images/nav/about.gif"; 
            img3off = new Image();
            img3off.src="http://www.impactfactory.com/images/nav/prog-at.gif";
            img4off = new Image();
            img4off.src="http://www.impactfactory.com/images/nav/library.gif";
            img5off = new Image();
            img5off.src="http://www.impactfactory.com/images/nav/new.gif";
            img6off = new Image();
            img6off.src="http://www.impactfactory.com/images/nav/more.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");
        }
}