The flight out of ATH where airport security confiscated my empty water bottles was ATH-ZRH this last summer. There was no misunderstanding -- the security person at ATH spoke excellent English, and I explained that my bottle was empty and even unscrewed the top, and held it upside down and shook it to show it was empty, but nothing doing, they took it away.

I also last year traveled through several other U.S. and European airports with empty plastic water bottles and had no problems taking them through security except at ATH.

Can anyone suggest a non-imbecilic reason for not allowing small empty clear plastic water bottles through security?