Configure JDBC adapter V4.2.1 to connect to DB2 V7.1 on AIX

We are trying to use the JDBC adpter to connect to DB2 V7.1 on the AIX. The Enterprise Integrator is v4.1.1 and the JDBC adapter is V4.2.1. We are not able to configure it to connect to the database. The error that we getting is “(314) Could not connect to database “jdbc:db2:txn” as user “db2inst1” (08001/0) No suitable driver”. What did we do wrong?
JDBC tab:
JDBC Driver : COM.ibm.db2.jdbc.app.DB2Driver
System NAme or IP Address: our AIX box ip address
Database User: db2inst1
Database Password :
Connection String (URL) : jdbc:db2:txn
Db2 Instance name with DB2 Connect:
JAVA tab:
Add to CLASSPATH: /usr/lpp/db2_07_01/java12/db2java.zip

Help?

Did you try using the ‘net’ driver instead of the ‘app’ driver.

FWIW, we could only connect w/ the ‘app’ driver to DB2 on OS390.

Where is the adapter installed?

We tried using the 'net’driver but still not succeed. The adapter is installed on the same machine where the DB2 resides.