// The popup window function
function PopupWindow(url, name, width, height, left, top)
{
   var winSizeStr = "location=0,status=0,scrollbars=1, width=" + width + ",height=" + height;
   mywindow = window.open(url, name, winSizeStr);
   mywindow.moveTo(left,top);
} 

var old_menu = ''; 

function menuclick( submenu ) 
{   
  if( old_menu != submenu )
  { 
    if( old_menu !='' )
    { 
      old_menu.style.display = 'none'; 
    } 
    submenu.style.display = 'block'; 
    old_menu = submenu; 
  }
  else
  { 
    submenu.style.display = 'none'; 
    old_menu = ''; 
  } 
}