Upgrading Spamassassin Debian Wheezy to Jessie

After the upgrade of Wheezy to Jessie, Spamassassin is not added to the startup services. Hence if you were using it before in your mail setup, you will run into the following error in /var/log/syslog

spamc: connect to spamd on ::1 failed, retrying (#1 of 3): Connection refused
spamc: connect to spamd on 127.0.0.1 failed, retrying (#1 of 3): Connection refused

Debian has a similar bug filed (#764438), even after a fresh reinstall.

So what is the solution

Simply activate Spamassassin via systemctl enable spamassassin