The last word that I have seen is that wine is okay, but that beer and hard liquor are not. Also, i understand that Princess began searching more thoroughly for liquor, at least in hand luggage, in the wake of 9/11.
Where does your cruise originate from? If sailing out of Seward, you should have no problem. If sailing out of Vancouver, you first have to go through Canadien customs. Most of the time this shouldn't be much of a problem, but you never know.