All,
The SpamAssassin team has released 3.1.8 maintenance release and this will be installed if you install/upgrade via the install script. The auto updaters will hopefully also receive this new version if the steps below have been followed.
It can also be downloaded directly from:
http://mirror.contribs.org/smeserver/contribs/swerts-knudsen/SpamFilter/Enjoy,
Jesper