We raised the issue of Dionyssos 11 with Jimmy and Spiro when we were there recently. They had no idea that it was showing up as not available for 2009 and asked Val (my wife) to show them on their computer, which she duly did.
They had to telephone Thomas Cook to find out what was happening (and remember, it's their property!!!!)
To cut a long story short, Dionyssos 1 and Dionyssos 11 are being marketed together as "Dionyssos". I suppose that if you just book Dionyssos there's no guarantee which one you will be allocated to, although I guess you could request 1 or 2.
Hope this helps if you are looking to book for next year.
Steve