browserName = navigator.appName;
browserVer = parseInt(navigator.appVersion);

if (browserName == "Netscape" && browserVer >= 3)
  version = "n3";
else 
  version = "n2";        

if (browserName == "Microsoft Internet Explorer" && browserVer >= 4)
  version = "n3";                       

if (version == "n3") {
  nav_abouton = new Image(0, 0);
  nav_abouton.src = "images/nav/nav_about_on.gif";
  nav_groupon = new Image(0, 0);
  nav_groupon.src = "images/nav/nav_group_on.gif";
  nav_listingson = new Image(0, 0);
  nav_listingson.src = "images/nav/nav_listings_on.gif";
  nav_closingson = new Image(0, 0);
  nav_closingson.src = "images/nav/nav_closings_on.gif";
  nav_urbanon = new Image(0, 0);
  nav_urbanon.src = "images/nav/nav_urban_on.gif";
  nav_testimonialson = new Image(0, 0);
  nav_testimonialson.src = "images/nav/nav_testimonials_on.gif";
  nav_presson = new Image(0, 0);
  nav_presson.src = "images/nav/nav_press_on.gif";
  nav_contacton = new Image(0, 0);
  nav_contacton.src = "images/nav/nav_contact_on.gif";
          
  nav_aboutoff = new Image(0, 0);
  nav_aboutoff.src = "images/nav/nav_about_off.gif";
  nav_groupoff = new Image(0, 0);
  nav_groupoff.src = "images/nav/nav_group_off.gif";
  nav_listingsoff = new Image(0, 0);
  nav_listingsoff.src = "images/nav/nav_listings_off.gif";
  nav_closingsoff = new Image(0, 0);
  nav_closingsoff.src = "images/nav/nav_closings_off.gif";
  nav_urbanoff = new Image(0, 0);
  nav_urbanoff.src = "images/nav/nav_urban_off.gif";
  nav_testimonialsoff = new Image(0, 0);
  nav_testimonialsoff.src = "images/nav/nav_testimonials_off.gif";
  nav_pressoff = new Image(0, 0);
  nav_pressoff.src = "images/nav/nav_press_off.gif";
  nav_contactoff = new Image(0, 0);
  nav_contactoff.src = "images/nav/nav_contact_off.gif";
}

function img_act(imgName) {
  if (version == "n3") {
    imgOn = eval(imgName + "on.src");
    document [imgName].src = imgOn;
  }
}

function img_inact(imgName) {
  if (version == "n3") {
    imgOff = eval(imgName + "off.src");
    document [imgName].src = imgOff;
  }
}