I get a connection and it returns data, but its all garbled. There appears to be some translation from the AS400 to Java that's not happening. Do I need to add a property type value in the hbm.xml map?

hibernate simply does not mess with the encodings or characters sets of the underlying jdbc driver/connection. If its happening through Hibernate, its also gonna happen through direct jdbc access through that same jdbc driver setup.

You probably want to get it working through direct jdbc first and then try accessing it through Hibernate.

I say encodings and charactersets simply because that is most usually the cause of this issue with databases and jdbc drivers in general.