Try that to an EM you just stole from. They will simply take the item back with a total lack of reguard for the event they are putting on(it was a Fel thief event)and the spirit of the game. The problem is the game has moved towards removing all common sense players and replacing them with players that push for more and more rules to protect them.
In this post:
http://vboards.stratics.com/1946654-post33.html
Petra states that the EMs aren't allowed to defend themselves here. (Presumably she means U-Hall.)
In this post, however, in the GL EM Forum:
http://vboards.stratics.com/1946641-post3.html
where it seems they are allowed to post, EM Elizabella posted the truth of the incident.
Mesanna took the item from him.
Here is EM Elizabella's reply, directly from the above link.
The object of the event was to steal grapes or to PvP with people who had stolen grapes. Mesanna took the item from you because it's not an item players are supposed to have. The item was of no use to you; you weren't able to move it around in your pack or remove it from your pack. Did you really want it stuck in your backpack for all eternity? Mesanna very kindly offered you a Festival of the Grapes stein, which you declined.
The game owns all items in the game, by definition. He stole something not part of the event, which he also couldn't move. If he couldn't move it, odds are he shouldn't have been able to steal it either. There's lots of bugs in this game. When you find one, sometimes you get to keep stuff from it, and sometimes you don't. And sometimes there's action taken against your account.
It's for the manufacturer to decide.
Mesanna is a direct representative of the manufacturer, and EM Elizabella is an indirect representative. Mesanna, as a representative of the manufacturer, decided.
You haven't said that any action was taken against your account so I presume it wasn't. I'd guess it is unlikely that would happen.
-Galen's player