Yesterday morning Nordhavn 55#45 Mondai Nai and Nordhavn 50#4 Java left North Palm Beach yesterday headed north for the spring and summer cruising season. They came up from the Florida Keys Wednesday with a stopover in Old Port Cove where Nordhavn Southeast salesman Fernando Diaz helped Java with a watermaker issue. Fernando sorted them out and got them on their way. The two boats will cruise in company until Java splits off in North Carolina. Mondai Nai plans to continue up to Virginia.