I'm seeing the same behavior, although I've disabled anonymous FTP on my server.
I've verified the local user I'm logging with has the correct PW. It's not network related, as I get the same error when connecting from the localhost.
Currently running package is from the @updates-testing repo:
vsftpd-2.3.4-6.fc16.x86-64
EDIT: Problem solved
Issue being tracked already in
Bugzilla here.
The workaround seems to be to add "/bin/bash" to your
/etc/shells file.
After I did this, I was able to log in to FTP with a local user account.