PASP

PASP is a highly efficient spam filter designed on Bayesian-like principles that can function as a POP3 proxy. It provides users with two primary methods to execute it. The first run can be through pasp.py as a pop3 proxy, with the email client configured to connect through PASP and insert headers for the email client to filter on. The second run can be achieved through the support for procmail and .forward support by passing through a script, allowing for email categorization, header insertion, and depositing in a folder for further processing by other mail software, thus enabling IMAP client support through server processing.

One can refer to the configuration file for support and utilize classify.py to get the job done. Notably, the latest version of PASP encompasses significant bug fixes. A critical bug in which spam wouldn't be categorized at all if the new streaming support was on got resolved, which had been a cause of worry for users. Another locking bug that had been an annoyance for a long time for many people got fixed. Unmistakably, it's a remarkable feat that this software worked on the author's machine and others', but now it runs flawlessly.