These laws would be applicable had intersango not voluntarily relinquished ownership of the coins. Intersango "agreed" by signing the coins away to bendavis that they are no longer the owners.
No, since it wasn't their intention. Bitcoin's technical implementation is of no relevance.
The technical implementation is of extreme relevance due to the nature of the transactions. Intent is not relevant. Bitcoin are like contracts. If you sign a contract you cannot back out of it simply by saying "i didnt intend to sign", you have already agreed to it. Dont intend to have things automatically signed for you? Then dont setup buggy software, simple.