Is it possible to install the VA using the same JBoss instance as the one used for the External RA GUI?
I'm also interested in the answer of your question. Have you already any success?
I didn't had much time to test this, but it looks like that the VA could provide all the features of the RA, from what I was able to seen on my tests most of the user-facing features seems available in the web interface.
An official statement on this would be much appreciated...