if (document.images) {
            img1on = new Image();
            img1on.src ="images/frar_tablec2h.gif";
            img2on = new Image();
            img2on.src ="images/frar_tablec3h.gif";
            img3on = new Image();
            img3on.src ="images/frar_tablec4h.gif";
            img4on = new Image();
            img4on.src ="images/frar_tablec5h.gif";
            img5on = new Image();
            img5on.src ="images/frar_tablec6h.gif";

            img1off = new Image();
            img1off.src ="images/frar_tablec2l.gif";
            img2off = new Image();
            img2off.src ="images/frar_tablec3l.gif";
            img3off = new Image();
            img3off.src ="images/frar_tablec4l.gif";
            img4off = new Image();
            img4off.src ="images/frar_tablec5l.gif";
            img5off = new Image();
            img5off.src ="images/frar_tablec6l.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");
        }
}