function changeClass(elem, className1,className2)
	{
	elem.className = (elem.className == className1)?className2:className1;
	}
	
function ToggleClass(id, class1, class2)
 {
  try
  {
   if(document.getElementById(id).className == class1)
   {
    document.getElementById(id).className = class2;
   }
   else
   {
    document.getElementById(id).className = class1;
   }
  }

  catch(e)
  {
     window.alert(e.description);
   }
 }