I was refused bag checkin at UAL conter in LAX because my luggage contained alchohol, which was sealed and packed. I followed with UA CR, and this was the responce:

"Our policy maintains that wine will be accepted as checked baggage provided it is wrapped in special packaging. The wine should be encased in styrofoam, which is moulded to the bottle's shape."

"- ALCOHOL (BEER/WINE/SPIRITS OR NON-ALCOHOLIC BEVERAGES) MAY BE ACCEPTED AS CHECKED BAGGAGE PROVIDED:
- GLASS CONTAINERS: MUST BE IN SPECIAL PACKAGING:
- STYROFOAM TYPE INSERTS MOULDED TO THE BOTTLE SHAPE
WHICH COMPLETELY ENCLOSES THE BOTTLE. "