if (document.images) {
    // preload the alternate images offscreen
   homeon = new Image();
   homeon.src = "images/home-on.gif";
   portfolioon = new Image();
   portfolioon.src = "images/portfolio-on.gif";
   designon = new Image();
   designon.src = "images/design-on.gif";
   hostingon = new Image();
   hostingon.src = "images/hosting-on.gif";
   ecommerceon = new Image();
   ecommerceon.src = "images/ecommerce-on.gif";
   programon = new Image();
   programon.src = "images/program-on.gif";
   domainon = new Image();
   domainon.src = "images/domain-on.gif";
   contacton = new Image();
   contacton.src = "images/contact-on.gif";
   homeoff = new Image();
   homeoff.src = "images/home-off.gif";
   portfoliooff = new Image();
   portfoliooff.src = "images/portfolio-off.gif";
   designoff = new Image();
   designoff.src = "images/design-off.gif";
   hostingoff = new Image();
   hostingoff.src = "images/hosting-off.gif";
   ecommerceoff = new Image();
   ecommerceoff.src = "images/ecommerce-off.gif";
   programoff = new Image();
   programoff.src = "images/program-off.gif";
   domainoff = new Image();
   domainoff.src = "images/domain-off.gif";
   contactoff = new Image();
   contactoff.src = "images/contact-off.gif";
}
function imgAct(imgName) {
  if (document.images) {
     document[imgName].src = eval(imgName + "on.src");
 }
}
function imgInact(imgName) {
  if (document.images) {
     document[imgName].src = eval(imgName + "off.src");
 }
}