Ah, yes, memories of one of my international etiquette major phucqueuppes.

I had no idea that dinner was automatically "eve" (as opposed to saying specifically "xmas eve" dinner in the US). When I called my amigo and said "nos vemos maņana" and he thought I'd be there in a few hours and I said I couldn't ... things you can laugh about years later. We did end up having a nice dinner the next evening.