This bug was marked as "fixed" but I see this problem in 2.1.7. I suspect it has something to do with me using SSO. Since users are created automatically instead of though JForum's sign-up system, perhaps it doesn't properly update the "newest registered user" info. It seems to only get updated when I restart the servlet container.
I can reproduce this. I've been displaying the same "newest registered user" for some weeks. After reading this thread, I restarted tomcat, and the value got updated. I use cookie-based SSO.
Should I file a new bug report, or do we reopen the old one?