function right(e) {
   if (navigator.appName == 'Netscape' && (e.which == 3 || e.which == 2))
      return false;
   else if (navigator.appName == 'Microsoft Internet Explorer' && (event.button == 2 || event.button == 3)) {
      alert(" Acesso Negado!\n BraZip Tecnologia " );
      return false;
   }
   return true;
}

document.onmousedown = right;
document.onmouseup = right;

if (document.layers) 
   window.captureEvents(Event.MOUSEDOWN);
if (document.layers) 
   window.captureEvents(Event.MOUSEUP);
   
window.onmousedown = right;
window.onmouseup = right;