function disableImageCopy(event) {
	var msg;
	if (event.which == null)
		msg = (event.button == 4) ? "middle" : "This image is copyright material.  Please click on 'Buy This Photo' to purchase a copy.";
	else
		msg= (event.which < 2) ? "left" : ((event.which == 2) ? "middle" : "This image is copyright material.  Please click on 'Buy This Photo' to purchase a copy.");
	if(msg == 'left' || msg == 'middle')
		onmouseup=dontAllow;
	else
		alert(msg);
	dontAllow(event);
}

function dontAllow(event) {
	if (event.preventDefault)
		event.preventDefault();
	else
		event.returnValue = false;
	return false;
}