Using Oracle Users in Realms and DataSource.getConnection

Question

Is it possible to authenticate using an Oracle User via JAASRealm and also retrieve connections specific to that user from a DataSource?
I currently have an application which doesn't use either, but rather sets up a OracleDataSource. So basically I just want to allow the container to administer both the authentication and data source setup, while still allowing the getConnection(user,password):
CODE
ocpds = new OracleConnectionPoolDataSource();
ocpds.setURL(connectionString);
ocpds.setConnectionProperties(props);
ods = new OracleDataSource();
ods.setURL(connectionString);
ods.setConnectionCachingEnabled(true);
ods.setConnectionProperties(props);
// Pool and Cache
Properties poolProps = new Properties();
poolProps.setProperty("AbandonedConnectionTimeout", "60");
poolProps.setProperty("InactivityTimeout", "5");
poolProps.setProperty("TimeToLiveTimeout", "60");
poolProps.setProperty("ConnectionWaitTimeout", "60");
ods.setConnectionCacheProperties(poolProps);
ods.setConnectionProperties(props);
Util.logln("Connection Cache Properties");
cache = OracleConnectionCacheManager.getConnectionCacheManagerInstance();
cache.createCache(cacheName, ods, poolProps);
cache.setConnectionPoolDataSource(cacheName, ocpds);
........later in the BatCave (JSP or a servlet).....
conn = (OracleConnection) ods.getConnection(username, password);
ENDCODE
This section from OAS Containers for J2EE Services Guide worries me:
(from: http://download-east.oracle.com/docs/cd/B14099_19/web.1012/b14012/datasrc.htm#sthref572 )
Using Different User Names for Two Connections to a Single Data Source
When you retrieve a connection from a DataSource object with a user name and password, this user name and password are used on all subsequent connection retrievals within the same transaction. This is true for all data source types.
For example, suppose an application retrieves a connection from the jdbc/OracleCMTDS1 data source with the scott user name. When the application retrieves a second connection from the same data source with a different user name, such as adams, the second user name (adams) is ignored. Instead, the original user name (scott) is used.
Thanks for reading all of this, and I appreciate any help!

Answer 1

Update:
I'm still not quite sure what to do. Where I am now:
1. I don't know how to authenticate against Oracle database users (non-ldap) via JNDI/JAAS/whatever
2. Proxy authentication (ALTER USER...CONNECT THROUGH...) seems to be promising for using connection pools, and in addition, once realm authentication happens, I can just pass the username and piggyback on the middletier connection without knowing the password used in authentication
3. I'm not sure if proxy addresses the issue that OAS Containers for J2EE Services Guide talks about in the original post
4. I'd prefer not to use OID
Again, if you have any little information, I'd really like to hear it.