Hi Joachim,
check-valid-connection-sql seems to validate in JBoss 3.2.3 only if it
is a subelement of local-tx-datasource or if xa-datasource is used.
If it is used as a subelement of tx-connection-factory (as we do it),
then it doesn't (as far as we found out).
It seems that the validation only works if Jaybird is engaged via JBoss
JDBC-JCA wrapper.
If JayBird is used directly as JCA/JDBC-Driver then there is no
validation with check-valid-connection-sql.

Regards
Josef Gschwendtner