currentExpanded=0;
collapsePrevious=0;

function ExpandNode(nodeId){
  clickedElement=document.getElementById(nodeId).style;
  if (!clickedElement)
    clickedElement=document.all.nodeId.style
  if (!clickedElement)
    return 1
  if (clickedElement.display=="block")
  {
    clickedElement.display="none";
    document.getElementById('img_'+nodeId).src = "/static/img/plus.gif";
  }
  else {
    if ((currentExpanded) && (collapsePrevious))
      currentExpanded.display="none"
    currentExpanded=clickedElement;
    currentExpanded.display="block";
    document.getElementById('img_'+nodeId).src = "/static/img/minus.gif";
  }
  ToggledAlready=1;
}