Most cruise lines will do the same.
You MUST tell them well in advance about the special needs and not wait until you board the ship.
They will make sure they have enough gluten free lactose free foods or whatever the food allergy is for the passenger
Alexandr Pushkin, Carnival-Holiday, HAL-(old)Westerdam, Orient lines-Marco Polo, Royal Olympic-Olympic, NCL-Dream, Dawn-Princess, ACCL-Grande Caribe, Oceania-Insignia (3), Regatta(4) Marina (1) St Lawrence Cruise Lines-Canadian Empress
Scenic River cruise June 11,2012