postfix-2.0.16-1 was added as id #17 to the fedora update list, this was to fix: https://bugzilla.redhat.com/bugzilla/show_bug.cgi?id=108960
There has been some limited testing by users reporting the bug who report success, but additional testing would be prudent. The fundamental change was to move from the .14 to .16 minor upstream rev to pick up an upstream bug fix.