if (window.Event) 
  document.captureEvents(Event.MOUSEUP); 
  function nocontextmenu()  
   {
    event.cancelBubble = true
    event.returnValue = false;
    return false;
   }
  function norightclick(e)	
   {
    if (window.Event)	
     {
      if (e.which == 2 || e.which == 3)
      return false;
     }
    else
    if (event.button == 2 || event.button == 3)
     {
      event.cancelBubble = true
      event.returnValue = false;
      return false;
     }	
   }
document.oncontextmenu = nocontextmenu;		
document.onmousedown = norightclick;