Thanks for your help. Instead of working my way out, I got back to the standalone version in order to validate the solution with IronJacamar.
I could do a lookup on the "TransactionManager", but as you told me, its integration is special.
I can see in the logs that my connector is well deployed (ManagedConnectionFactory and so on...), but can't do a lookup on the factory.
I assume I can't do it the same way than the tx beans... I can browse it from the console. Is there a way to do it from JMX ? Do I have to configure something else ?