function bderecho(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("PRGF");
		return false;
	}
	return true;
}
if (document.layers) window.captureEvents(Event.MOUSEDOWN);
window.onmousedown=bderecho;
document.onmousedown=bderecho;