Oracle Wallet and Comodo Certificate

Does anyone have experience in connecting to a server with a Comodo Certificate from an Oracle Wallet system?

We have a credit card processing system that needs to reply back to a web server with client number, transaction number and transaction amount (why it needs to be secure is not clear to me…)

The Oracle administrator says that Oracle Wallet won’t connect to the web server because we have a Comodo certificate and the we now have to go buy a Verisign certificate.

It seem to me they should be able to add Comodo as a trusted authority (?!?)