function showHideSpoiler(spoiler)
{
  for (var i=0; i<spoiler.childNodes.length; i++)
    if (spoiler.childNodes[i].style.display=='block' && spoiler.childNodes[i].className == "spoilerArea")
      spoiler.childNodes[i].style.display='none';
    else if (spoiler.childNodes[i].className == "spoilerArea")
      spoiler.childNodes[i].style.display='block';
    else if (spoiler.childNodes[i].tagName.toUpperCase() == "A") {
      var img = spoiler.childNodes[i].firstChild;
      var parts = img.src.split("/");
      var pic = "";
      parts[parts.length-1] = (parts[parts.length-1] == "expand.jpg") ? "collapse.jpg" : "expand.jpg";
      for (var j=0; j<parts.length; j++)
          pic += (j==0) ? parts[j] : "/" + parts[j];
      img.src = pic;
    }
}