I am facing a similar problem - the only difference is mail is nowhere to be found (not even as a spam). However, the email is present under the James Server file system; local inbox of the user - james-2.3.2\apps\james\var\mail\inboxes\<testuser>
DNS is configured as mentioned in the documentations. Is there a specific change needed to send this email across to the Internet?
What do you have in that there bucket? It wouldn't be a tiny ad by any chance ...
Building a Better World in your Backyard by Paul Wheaton and Shawn Klassen-Koop