It's an incredible pita... Also had to call several times, as they simply don't read the tickets/emails.
Once ur payment gets rejected about 2 or 3 times, theres no reason to continue trying, as the account is locked, and they need to check it and unlock it.

Also had problems while faction changing my last shaman, the 5th. Yesterday i tested my luck and payed all my accounts at the same time, and it worked out, yay!

See u tonight!