Enabling JDBC Adapter hangs WM Server

I am trying to configure a JDBC Adapter DB connection. I am able to save the config info successfully but when I try to enable the JDBCAdapter connection, the browser hangs, which also prevents the admin window from displaying the jdbc connections for other people logged on to the admin web page but we can still go to other windows like Error, Audit, WmDb. When this happens, I can’t shut down the server through the browser nor using webm.sh stop. I have to kill the process. Once server is restarted, I can see the JDBCAdapter connections. WmDB connection works fine for the same database using COM.ibm.db2.jdbc.app.DB2Driver driver and db URL jdbc:db2:DB2Dev.

Config info:
webMethods version 6.1 on Unix (also tried on Windows)
DB2 on the mainframe
Driver type 2
DataSource ClassName – COM.ibm.db2.jdbc.DB2DataSource
LOCAL_TRANSACTION (also tried NO_TRANSACTION)
ServerName: full server name (also tried IP)
User ******
Password ******
DatabaseName: DB2Dev
Port Number: *****

Log:
2005-01-07 10:45:19 EST [ART.0118.5505V1] Adapter Runtime (Connection): Starting
connection db2:testcon.
2005-01-07 10:45:19 EST [ART.0118.5505V1] Adapter Runtime (Connection): Starting
connection db2:testcon.
2005-01-07 10:45:20 EST [ART.0118.5517V1] Adapter Runtime (Connection): Creating
connection manager properties: >>>BasicData:poolable=true,minimumPoolSize=1,max
imumPoolSize=10,poolIncrementSize=1,blockingTimeout=1000,expireTimeout=1000,sele
ctionSize=1,poolOnCommit=true<<<.

Any help would be appreciated.

Thanks,
Harsha