Sorry I took so long to reply. The forum email notification apparently didn't work for me, and I had moved onto other NullPointerExceptions since then :-) But since you took the trouble to reply:
The solution was not easy to figure out. I thought that EMBEDDED and LOCAL setting for the broker are supposed to be the same barring the separate JVMs. Changing the one word EMBEDDED to LOCAL in the domain.xml switched that NullPointerException off and on reproducibly for my then configuration. I have for the last week been working in LOCAL mode as a result which worked fine, and my configuration has changed significantly since then. I switched back to LOCAL for the last couple of hours, but unfortunately could not reproduce the problem in my current configuration, so it may have been a combination of LOCAL and I believe a misconfiguration in the sun-ejb-jar.xml, and obviously related to MDBs.
I hope that helps, and if I see the error again, I will follow the instructions you provided in this post.
But I must be the man for NullPointerExceptions, because I'm staring at another right now. I'll post it in a separate thread, since it's not related to this area.
Joe
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