Until very recently there was a bug in all jboss 3 and 4 versions that caused these default values to be ignored, and only the values in the mbean configuration to be used. I think I have it fixed in all cvs versions so the default values from ra.xml are used unless overridden by values in the mbean configuration that actually deploys your ManagedConnectionFactory instance.
I don't think this is in any binary releases yet.
Humm, well OK, I'll check out the latest JBoss source. However, I'm still unclear on how the values from ra.xml become available to my ManagedConnectionFactory instance (in the debugged version). Does the deployer automatically call the corresponding set methods for each of these properties, or do I, as the creator of the ManagedConnectionFactory derived class have to do something to initialize them based on some system call, say in the class constructor?
The deployer sets values of all properties with values supplied in ra.xml or *-service.xml. Your adapter doesn't have to set anything itself.