|09:11 am - Merry Christmas, Happy Mithras Day, whatever|
I've always been laissez faire about holidays - why not celebrate them all? It would be one long party from October to January! If it isn't your specific holiday, just be happy that other people have reason to celebrate.
Yes, it sounds suspiciously like "Can't we all just get along?" but there's something to be said for asking that question, as open to mockery as it usually is.