if (document.images) {
  image1on = new Image();
  image1on.src = "../btn/111.gif";
  image1off = new Image();
  image1off.src = "../btn/1.gif";

  image2on = new Image();
  image2on.src = "../btn/222.gif";
  image2off = new Image();
  image2off.src = "../btn/2.gif";
  
  image3on = new Image();
  image3on.src = "../btn/333.gif";
  image3off = new Image();
  image3off.src = "../btn/3.gif";
  
  image4on = new Image();
  image4on.src = "../btn/444.gif";
  image4off = new Image();
  image4off.src = "../btn/4.gif";

  image5on = new Image();
  image5on.src = "../btn/555.gif";
  image5off = new Image();
  image5off.src = "../btn/5.gif";
  
  image6on = new Image();
  image6on.src = "../btn/666.gif";
  image6off = new Image();
  image6off.src = "../btn/6.gif";

  image7on = new Image();
  image7on.src = "../btn/777.gif";
  image7off = new Image();
  image7off.src = "../btn/7.gif";

  image8on = new Image();
  image8on.src = "../btn/888.gif";
  image8off = new Image();
  image8off.src = "../btn/8.gif";

  image9on = new Image();
  image9on.src = "../btn/999.gif";
  image9off = new Image();
  image9off.src = "../btn/9.gif";

  image10on = new Image();
  image10on.src = "../btn/101.gif";
  image10off = new Image();
  image10off.src = "../btn/10.gif";

  image11on = new Image();
  image11on.src = "../btn/112.gif";
  image11off = new Image();
  image11off.src = "../btn/11.gif";

  image12on = new Image();
  image12on.src = "../btn/122.gif";
  image12off = new Image();
  image12off.src = "../btn/12.gif";
}
function turnOn(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "on.src");
  }
}
function turnOff(imageName) {
  if (document.images) {
    document[imageName].src = eval(imageName + "off.src");
  }
}