Following the usual paradigm:
1. Bang head on wall for hours
2. Post message to forum
3. Immediately figure out the answer
4. Post answer as reply to original post
5. Realize no one will ever read it anyway :)
OK, in order to do what I wanted (which is to log DEBUG messages from my app to the console), I needed to set up my own ConsoleAppender, I could not reuse the same one that JBoss was using as that Appender had a threshold associated with it.
Here is the relevant section of my log4j.xml:
<!-- The default pattern: Date Priority [Category] Message\n -->
Hope this is useful to someone...
it was useful for me :-)