if (document.images) {

            img1on = new Image();      
            img1on.src = "http://www.tiken-fukui.com/img/gnav_hp_ovr.gif";
            img2on = new Image();      
            img2on.src = "http://www.tiken-fukui.com/img/gnav_lstngs_ovr.gif";
            img3on = new Image();      
            img3on.src = "http://www.tiken-fukui.com/img/gnav_cmpny_ovr.gif";
            img4on = new Image();      
            img4on.src = "http://www.tiken-fukui.com/img/gnav_srvcs_ovr.gif";
            img5on = new Image();      
            img5on.src = "http://www.tiken-fukui.com/img/gnav_blog_ovr.gif";
            img6on = new Image();      
            img6on.src = "http://www.tiken-fukui.com/img/indc_tit_pg_ovr.gif";
            img7on = new Image();      
            img7on.src = "http://www.tiken-fukui.com/img/indc_end_pg_ovr.gif";

            img1off = new Image(); 
            img1off.src = "http://www.tiken-fukui.com/img/gnav_hp_def.gif";
            img2off = new Image();      
            img2off.src = "http://www.tiken-fukui.com/img/gnav_lstngs_def.gif";
            img3off = new Image();      
            img3off.src = "http://www.tiken-fukui.com/img/gnav_cmpny_def.gif";
            img4off = new Image();      
            img4off.src = "http://www.tiken-fukui.com/img/gnav_srvcs_def.gif";
            img5off = new Image();      
            img5off.src = "http://www.tiken-fukui.com/img/gnav_blog_def.gif";
            img6off = new Image(); 
            img6off.src = "http://www.tiken-fukui.com/img/indc_tit_pg.gif";
            img7off = new Image(); 
            img7off.src = "http://www.tiken-fukui.com/img/indc_end_pg.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");
        }
}