var message="Sorry, right-click is disabled.";

///////////////////////////////////
function clickIE4(){
  if (event.button==2){
    alert(message);
    return false;
  }
}

function clickNS4(e){
  if (document.layers||document.getElementById&&!document.all){
    if (e.which==2||e.which==3){
      alert(message);
      return false;
    }
  }
}

if (document.layers){
  document.captureEvents(Event.MOUSEDOWN);
  document.onmousedown=clickNS4;
} else if (document.all&&!document.getElementById){
  document.onmousedown=clickIE4;
}

document.oncontextmenu=new Function("alert(message);return false")