You can put it in your checked luggage. Besides, I know people who have accidently gotten water past the screeners. Remember, TSA are rent-a-cop drop-outs.
Celebrity Mercury - Hawaii
Princess Golden - Meaxican Riviera Oct/Nov '07
Norwegian Star - Mexican Riviera Oct '06
Carnival Ecstasy - Catalina/Mexico April '02
Disney Wonder - 3 day Bahamas Nov '99