Additional information is available at a previous version of this page
It is quite outdated. However, it may have some information which has not yet been incorporated into the current version.
1. FAQ
1.1. Where can I find the config files?
A: https://git.hcoop.net/hcoop/config/spamassassin.git contains the current spamd configuration, which is pulled into puppet using a git submodule.
Installation is handled using Puppet classes hcoop::service::mail::spamassassin::{client,server}, which is unfortunately only accessible to members with admin accounts currently.