Can you possibly try 4.0.3 to see if the problem persists there? That can rule out AS at the very least.
Unfortunately, upgrading is not an option right now. This is our test environment, which is a replica of our production environment, and there are a number of issues preventing us from upgrading past 3.2.6 at this time, although there is a team working on that. Our development environment is just a single JBoss app server with no web server or load balancing, so the problems we're having only appear in test. We need to change our development environment, but that's an issue we'll deal with after we've solved this problem, as it is preventing us from deploying applications to production.
Anyway, I'm starting to think that the issue is actually caused by the existence of the two web servers, so it may be that JBoss is actually properly configured. I set up two JBoss instances on my workstation, and configured Apache with load balancing the same way our test environment is set up, and I'm having no problems getting session replication working in that environment.
So for now I'm thinking this is not a JBoss issue, it's a problem with our over-architected environment.
I will post more later if I discover further problems that are definitely JBoss-related.
I am still curious about why the distributed apps won't display information in the web console. If I get time I will try setting up an instance of JBoss 4 on my workstation to see if it's an issue specific to 3.2.6, but right now I don't have time to do that.
Has anyone else seen this problem?