I have the same problem (not solved yet) with a 1-many relationship where the key of the "many" table is a compound key containing the parent table key plus an additional field. JBoss adds an extra field to make the relationship but the value is duplicated.
In addition, if I specify to use an existing field for the relationship then table creation fails with an illegal SQL DDL statement.
Do somebody knows how to force this kind of relationships to use existing fields?
I'm using Jboss 3.0.4 with MSDE2000 and MS jdbc driver for SQL2000.