var message="Please purchase these images from Digihouse" 

function click(e) {
	if (document.all) {
		if (event.button == 2) {
			alert(message);
		return false;
		}
	}
	if (document.layers) {
		if (e.which == 3) {
			alert(message);
			return false;
		}
	}
}
if (document.layers) {
	document.captureEvents(Event.MOUSEDOWN);
}
document.onmousedown=click;