Starting spamd: child process [22173] exited or timed out without signaling production of a PID file

I upgraded spamassassin and encountered an error when trying to start it.

[root@nelsoncli Mail-SpamAssassin-3.4.0]# /etc/init.d/spamassassin start
Starting spamd: child process [22173] exited or timed out without signaling production of a PID file: exit 255 at /usr/bin/spamd line 2960.
                                                           [FAILED]

Solution: Run sa-update.