if (document.images) {
        img1on = new Image();
        img1on.src = "images/nav_prod_ov.gif";
        img1off = new Image();
        img1off.src = "images/nav_prod_up.gif"

		img2on = new Image();
        img2on.src = "images/nav_spec_ov.gif";
        img2off = new Image();
        img2off.src = "images/nav_spec_up.gif"
		
		img3on = new Image();
        img3on.src = "images/nav_inst_ov.gif";
        img3off = new Image();
        img3off.src = "images/nav_inst_up.gif"
		
		img4on = new Image();
        img4on.src = "images/nav_abt_ov.gif";
        img4off = new Image();
        img4off.src = "images/nav_abt_up.gif"
		
		img5on = new Image();
        img5on.src = "images/nav_cont_ov.gif";
        img5off = new Image();
        img5off.src = "images/nav_cont_up.gif"
		
		img6on = new Image();
        img6on.src = "images/nav_faq_ov.gif";
        img6off = new Image();
        img6off.src = "images/nav_faq_up.gif"
		
		img7on = new Image();
        img7on.src = "images/nav_ordr_ov.gif";
        img7off = new Image();
        img7off.src = "images/nav_ordr_up.gif"
}
function imgSwap (imgName,imgFile)  { 
        if (document.images)  {
                document.images[imgName].src = eval (imgFile + ".src");
        }
}