YOu can update hibernate.properties.
You can update xxx-ds.xml,hibernate.properties and standardjbosscmp-jdbc.xml .
I wouldn't be surprised if one of those configuration files could solve my problem, but I looked at them before posting my question. The reason I'm asking is that I'm flumoxed. You'd think this kind of thing would just work out of the box, or it would be a FAQ.
I'm tempted to fall back to using JBoss as just a simple RPC (RMI) engine, and do all the JDBC myself. I can at least figure out how that works. I was kinda hoping that entity beans and hibernate would simplify things, but if they just make it harder, why bother?