Yes. They come under the dangerous goods restictions - the restriction being that they can be in containers no larger than 2 litres. Officially, they are permitted in checked or hand baggage but of course they would fall foul of the current liquids policy in hand luggage.
Another interesting fact is that (if it wasn`t for the current liquids policy) ICAO laws say that you can take up to 5 litres of booze onto a flight. I have done that myself when I brought back a 5 ltr wine box from S Africa.