Yes, ALWAYS start with a configuration file that comes with your new jboss version and check if it matches your old one.
You can still use *-service.xml files in 3.1, although you will have to move the jndi name attribute to the connection manager mbean, but I recommend you use the simplified *-ds.xml file format.
Is there any documentition on this? (There's none in the All Docs Dumscription from a couple of days ago.)
I tried editing the oracle-ds.xml, removing the oracle-service.xml and restarting. No exception on startup, but still couldn't get a DB excpetion. Probably my guesswork as to how to use the new config style is wrong.
Should have said that I put the oracle-ds.xml in the deply dir