var clicked="";

function chgBg(color,name,click){
  var old="";
  if (clicked==name)
    return false;
  if (click==true){
    if (clicked!=""){
      old=clicked;
      clicked="";
      chgBg('#336699',old,false);
    }
    clicked=name;
  }
  if (document.all)
    document.all[name].style.backgroundColor=color;
  else if (document.getElementById)
    document.getElementById(name).style.backgroundColor=color;
  else if (document.layers)
    document.layers[name].bgColor=color;
}