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;
    } 

} 

if (document.layers)
  document.captureEvents(Event.MOUSEDOWN); 
 
document.oncontextmenu = nocontextmenu; 
document.onmousedown = norightclick; 
document.onmouseup = norightclick;