function click(e) {
  if (document.all) {
  if (event.button == 2 || event.button == 3) { oncontextmenu = "return false"; } }
  if (document.layers) {
   if (e.which == 3) { oncontextmenu = "return false"; } } }
if (document.layers) { document.captureEvents(Event.MOUSEDOWN); }
document.onmousedown = click;
document.oncontextmenu = new Function("return false;");