I have the same problem, could you solve it?
Currently, JBoss does not support this functionality and it may never be implemented. See this thread on the reasons why standard connection technologies do not work when the client is in a JVM external to the connection pool.
Weblogic provides a solution to this through a proprietary RMI proxy implementation. However, from a performance perspective, it is difficult to see whether you make any real gains as you trade off connection cost times to the database through pooling, with the connection cost to the proxy and the cost for operating through two across-the-wire links to the end target.
It is possible that in the long-term the AOP infrastructure may eventually allow your standard Java classes to access pools as they will be bound in the same VM. Have to wait and see how things develop.