Does anyone know the solution for this problem ? I've the same now with JBoss 3.2.3, but with 3.2.1 version there were no problem.
Ok I've "resolved" the problem, turning back to 3.2.1 version. Anyway the problem was this:
an ejbql query like this:
SELECT DISTINCT OBJECT(o)
FROM PortatoreConoscenza AS o
WHERE o.portConOrg IS EMPTY
generates a sql query like this:
SELECT DISTINCT t0_o.ID_PORTCON
FROM portatori_conoscenza t0_o
WHERE ((t1_o_portConOrg.ID_PORTCON IS NULL AND t1_o_portConOrg.ID_ORG IS NULL))
which is obviously incorrect (t1_o_portConOrg is not in the FROM clause).
Can I suppose this is a bug in 3.2.3 version of JBoss ? I've not tested 3.2.2 version.