Problem with registration

Hello,

I have been trying to buy my ticket for this year's conference but when
trying to pay with my card from Eurobank (eurobank.gr) I get an error:
"The card was declined". I have since tried to pay with another card I
have (also from Eurobank), which was also declined. Searching the
mailing list, I noticed that this has been reported before with cards
from another Greek bank. Considering I cannot pay with these cards, is
there another way I can register?

--
Spiros Klouvas
Computer Science student