I think you could bring 2 bottles each. It doesn't specify any quantity on their website. This is what I found:
We kindly request that you do not bring alcoholic beverages (other than wine and/or champagne) onboard for consumption. Alcoholic beverages that are purchased duty free from the ship's gift shop or at ports of call will be collected for safekeeping and delivered to your stateroom on the last day of the voyage. A member of our Security Staff will be at the gangway to assist with the storage of your alcoholic beverage purchases.
Teresa and Larry
#36-Carnival Splendor 9/16/12
7 night Mexican Riviera
#37-Allure of the Seas 11/11/12
7 night Eastern Caribbean
We did the Crown last year out of San Juan. In their screening process, they have a "duty Free shop" We ended up getting about four cases of wine, ( between 12 of us) and four bottles of Rum. had NO problems at all. We went through the wine each night getting ready for dinner, and always had at least three bottle at our table.
5 time CARINIVAL CRUISER (Last on Glory 6/08 Next not sure)
3 time PRINCESS CRUISER( Last on Crown 4/08, Next Sapphire 3/10,)
5 time visitor to JAMAICA ( Love Ochi, and Negril)