XADataSourceLoader and the XADataSourceImpl are gone from jboss 3. The basic pooling code is the same, and IMHO excessively complex and bug-ridden. The "JDBC" stuff is more or less replaced by the NoTrans ConnectionManager.
I would certainly prefer that effort be put into making sure the connector code is spec compliant and works, however this may not line up with your immediate needs ;-) I do think the connector framework makes more sense than the 2.4 code it replaces (i.e., I can figure out what the connector code does, and I can't understand XADataSourceLoader).
David, thanks for the reply - I suspected the connector code was replacing the existing datasource classes. I managed over a lost weekend a couple months ago to figure out what XADataSourceLoader was doing - my goal was to figure out why userid/password were not being correctly honored. I managed to do that, and that is the change I wanted to get into the jbosspool classes. Rather than expend energy on dead-end code, I'll start looking into the connector code.