ImageList = new Array ();
  for (i in ImageNames) {
    ImageList[i] = new Image();
    ImageList[i].src = "/images/" + ImageNames[i] + "_on.png";
  }
  for (j in ImageNames) {
    ImageList[j+i] = new Image();
    ImageList[j+i].src = "/images/" + ImageNames[j] + "_out.png";
  }

  function imgSwap(Name,postfix, lang) {
    if (lang) {lang =lang+'_';} else {lang="";}
    document.images[Name].src = '/images/' + lang + Name + '_' + postfix + '.png';
}