We are having the same problem on a clients server. We moved them from Redhat 7.3 to Debian 3.1. The data did not change, it is mounted over NFS. The error we get is the "There has been an error processing your credit card. Please try again." I have called Authorize.net several times and they tell me they can't help us since there is no error code. This is with a default 2.2 install. We tried the newer authorize.net module which produced an error code 103, which doesn't make sense since we are posting our username and fingerprint to the authorize.net server when the checkout confirmation is completed.

Any help on this would be appreciated.