We need a db2-jdbc2-service.xml to be ship with jboss-4.2.x (and also jboss-4.0.x) to support DB2 databases.

To start with i copied oracle-jdbc2-service.xml to db2-jdbc2-service.xml and made a few SQL changes.

1.) With DB2 all primary keys should be explicitly mentioned NOT NULL
I added NOT NULL to TXID column.
CREATE TABLE JMS_TRANSACTIONS ( TXID INTEGER NOT NULL, PRIMARY KEY (TXID) )

WIth this persistance configurations work with DB2 8.0

2.) With DB2 7.2 the following query throws an error:
db2 => CREATE TABLE JMS_MESSAGES (MESSAGEID INTEGER NOT NULL, DESTINATION VARCHAR(150) NOT NULL, TXID INTEGER, TXOP CHAR(1), MESSAGEBLOB BLOB, PRIMARY KEY (MESSAGEID, DESTINATION))

DB21034E The command was processed as an SQL statement because it was not a
valid Command Line Processor command. During SQL processing it returned:
SQL0604N The length, precision, or scale attribute for column, distinct type,
structured type, attribute of structured type, function, or type mapping
"MESSAGEBLOB" is not valid. SQLSTATE=42611