Kimmi,
I thought that Tommy Bahama / resort style shirts were acceptable for all nights - no jackets at all. i seem to remember Ngaire saying that Ken did not bring a jacket and that if that was the case, Marc was leaving his jacket home too. Frank would prefer no jacket, if it's acceptable, although, since I bought him the silk t-shirts for jacket required evenings, he doesn't mind as much as he used to. He wore a sport coat or suit and tie (he's a CPA) every day for 25 years. He's shed that now for the last 10 or so, but, he hates to wear a tie and coat unless it's absolutely required.