Das SSL Zertifikat ist von Comodo.
Auf dem Testshop ist natürlich kein SSL - vielen Dank für den Hinweis.
Hier das errorlog vom richtigen Shop:
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] PHP Fatal error: Uncaught exception 'Billsafe_Exception' with message 'Missing SSL transport support in PHP' in /var/www/web24/html/tierland/includes/classes/billsafe_2/HttpClient.php:55, referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] Stack trace:, referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] #0 /var/www/web24/html/tierland/includes/classes/billsafe_2/billsafe_2.php(112): Billsafe_HttpClient->__construct('https://sandbox...'), referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] #1 /var/www/web24/html/tierland/includes/modules/payment/billsafe_2.php(165): Billsafe_Sdk->callMethod('prevalidateOrde...', Array), referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] #2 /var/www/web24/html/tierland/includes/classes/payment.php(204): billsafe_2->selection(), referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] #3 /var/www/web24/html/tierland/checkout_payment.php(149): payment->selection(), referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] #4 {main}, referer: https://www.tierland.net/checkout_shipping.php
[Fri Jul 19 10:57:36 2013] [error] [client 79.236.26.212] thrown in /var/www/web24/html/tierland/includes/classes/billsafe_2/HttpClient.php on line 55, referer: https://www.tierland.net/checkout_shipping.php