UserTransaction and too many connections

Question

This might sound a bit weird. I am just looking for some quick pointers here if possible. The OC4J version in use is 9.0.4.0.0. I am doing something along the following lines in a struts action class.
1) UserTransaction txn = ctx.lookup("java:comp/UserTransaction");
2) Connection conn = dataSource.getConnection();
3) txn.begin();
4) ..StatelessSessionBean call which uses a few entity beans (Bean Managed)
5) Direct updates using conn (no commits in this).
6) txn.commit
My issue is with step 4 above. It does some updates and this results in close to 500 plus physical db connections getting created when in UserTransaction. The beans are normal usual beans and the whole process works without issues if I get rid of UserTransaction with less than 50 physical connections.
I am just not able to pinpoint what exactly might be going wrong in the beans that such a large number of connections get created when in UserTransaction.
The datasource is along these lines
     <data-source
          class="com.evermind.sql.DriverManagerDataSource"
          name="xxxDB"
          location="jdbc/xxxDBCore"
          pooled-location="jdbc/xxxDBCore_non_tx"
          xa-location="jdbc/xa/xxxDBXA"
          ejb-location="jdbc/xxxDB"
          connection-driver="oracle.jdbc.driver.OracleDriver"
          username="xxxxxxxx"
          password="xxxxxxxx"
          url="jdbc:oracle:thin:@1.2.3.4:1521:xxx"
          min-connections="10"
     />
I check for the number of physical connections using the oc4j option
-Ddatasource.verbose=true which prints out the information.
If I set the max-connections attribute on the datasource, I get a Timeout waiting for connection exception in the app.
If any of this rings a bell and if you have any thoughts or suggestions, I would really appreciate it.
Thanks in advance
best regards
-Sudhir

Answer 1

Just to add to my above post, the messages on the cnsole are along the lines of ...
null: Connection com.evermind.sql.DriverManagerXAConnection@189c9fe allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@12c820f
null: Connection com.evermind.sql.DriverManagerXAConnection@12c820f allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@10eb09e
null: Connection com.evermind.sql.DriverManagerXAConnection@10eb09e allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@16d7d9e
null: Connection com.evermind.sql.DriverManagerXAConnection@16d7d9e allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@e3f9e3
null: Connection com.evermind.sql.DriverManagerXAConnection@e3f9e3 allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@10382ca
null: Connection com.evermind.sql.DriverManagerXAConnection@10382ca allocated (Pool size: 0)
Created new physical connection: com.evermind.sql.DriverManagerXAConnection@17faec2
Why would the pool size be 0?