as far as logging, i think you can provide a log4j.properties in your EAR to adjust the default logging.
you should be able to identify the error in your entity annotations though.
ps. have you looked at jboss_home/server/***/log/server.txt?
Thanks for the help. I did end up finding out yesterday that $JBOSS_HOME/server/default/log/server.log had more detailed debugging information, particularly a DEBUG level Hibernate log. I also found that the default configuration in $JBOSS_HOME/server/default/conf/log4j.xml was filtering these messages from the console and that this could be changed there.
I also figured out my problem below - it was a table name clash that confused Hibernate. I had a many-to-many association between two entities that accidentally had the same name as another unrelated entity. Hibernate then would create a join table of the same name and get confused when making relationships. This is something to watch out for!