if (document.images) {

  img_nav_main_1on = new Image();
  img_nav_main_1on.src = "../_img/nav_main_1over.gif";
  img_nav_main_2on = new Image();
  img_nav_main_2on.src = "../_img/nav_main_2over.gif"; 
  img_nav_main_3on = new Image();
  img_nav_main_3on.src = "../_img/nav_main_3over.gif";
  img_nav_main_4on = new Image();
  img_nav_main_4on.src = "../_img/nav_main_4over.gif";
  img_nav_main_5on = new Image();
  img_nav_main_5on.src = "../_img/nav_main_5over.gif";
  img_nav_main_6on = new Image();
  img_nav_main_6on.src = "../_img/nav_main_6over.gif";
  

  img_joinon = new Image();
  img_joinon.src = "../_img/g_join_on.gif";

  img_nav_main_1off = new Image();
  img_nav_main_1off.src = "../_img/nav_main_1off.gif";
  img_nav_main_2off = new Image();
  img_nav_main_2off.src = "../_img/nav_main_2off.gif";
  img_nav_main_3off = new Image();
  img_nav_main_3off.src = "../_img/nav_main_3off.gif";
  img_nav_main_4off = new Image();
  img_nav_main_4off.src = "../_img/nav_main_4off.gif";
  img_nav_main_5off = new Image();
  img_nav_main_5off.src = "../_img/nav_main_5off.gif";
  img_nav_main_6off = new Image();
  img_nav_main_6off.src = "../_img/nav_main_6off.gif";
  
  img_joinoff = new Image();
  img_joinoff.src = "../_img/g_join_off.gif";

}

function changeImages() {
  if (document.images) {
    for (var i=0; i<changeImages.arguments.length; i+=2) {
      document[changeImages.arguments[i]].src = eval(changeImages.arguments[i+1] + ".src");
    }
  }
}