The issue here is in fail2ban 0.8.14 fail2ban upstream now fails to start if a log file it should monitor is not there. The FTP log file is not created until someone starts FTP and that is something they pick to do in sysadmin if they want to enable FTP and on our dev boxes it was started so their was a log file so it was never picked up in Q/A. We have published a new fail2ban that will verify all log files are their on install and if not touch the file to create it so fail2ban will start.
As stated this would of been resolved last week had a bug report been opened as it would of been picked up by a developer. Please make sure to use the issue tracker for all bugs regardless of how small or large they are. That is where all the devs monitor issues.