The main one is specify that it is a collectable and not for consumption.
Basically Ebay states...
eBay does not permit the sale of alcoholic beverages, except for certain sales of collectable containers. Further, non-UK members may not conduct alcohol sales with any eBay member residing in the United Kingdom.
Breaches of this policy may result in a range of actions, including:
Listing cancellation
Limits on account privileges
Account suspension
Forfeit of eBay fees on cancelled listings
Loss of PowerSeller status
However ebay permits the sale of ...
Collectable Containers
eBay will permit sales of unopened collectable containers that still contain alcohol as long as each of the following conditions are met:
The value of the listed item is in the collectable container, not its contents. Thus bottles of wine are not permitted because their value is based on the wine in the bottle, and not the bottle itself.
The listing description should state that the
container has not been opened, but that any incidental contents are not intended for consumption.
The item must not be available at any retail outlet, and the container must have a value that substantially exceeds the current retail price of the alcohol in the container.
Sellers should take steps to
ensure that the buyer of these collectables is of lawful age in the buyer and seller's jurisdiction (generally 18 years old in the UK and Republic of Ireland, 21 years old in the US).
Buyers and sellers must ensure that the sale complies with all applicable laws and delivery regulations in carrying out the transaction.
See here
http://pages.ebay.co.uk/help/policies/alcohol.html
You can cut and paste this and place it at the end of your advertised item.