I use a base class with many classes extended from it. The discriminator column was created as only a varchar(10). Needless to say, one of the classes had a longer discriminator value. Luckily it was very easy to pick up on. I changed the column to varchar(36), fixed the entry and all was well.
The IDE is JBoss 1.5 milestone 1, the JBoss version 4.0.3, the database MySQL 4.0.24 and the OS Linux
How do I tell JBoss to create a bigger column? 10 is obviously the default size. Maybe it should be a bit bigger.