Projects / Clement


Clement is an email server application. Its main function is to block unwanted mail (spam) as soon as possible in the email exchange process. It accepts or rejects email while the SMTP session, initiated by the email sender, is still pending, accepting legitimate email messages without the need to return an error status to non-existent or "borrowed" return address later. Clement can operate in two modes, either as a standard MTA (as sendmail, Postfix, Exim, Exchange, etc.) to store email in the recipient's own area, or to transmit the mail to an another SMTP server acting as smart spam filtering device. Each email domain name Clement knows about can be treated in one of these two modes depending on the group to which the domain name has been set. Each message is verified by a virus scanner (ClamAV) while the SMTP connection is still open, but the refusal of mail and the reason for refusal is notified to the actual sender. Mail management is done via a Web interface and can be delegated to three administrative levels (Root-Admin, Group-Admin, Domain-Admin). Standard users can access their own logs (sent email status, email rejected, quarantined email, etc.). With this interface, the user can handle the rejection and acceptance of mail. Users who are level "Admin" can access the session logs (via the Web interface). Clement uses a SQL database (PostgreSQL, MySQL) to store and manage logs, user profiles, and dynamic management of directives concerning the sender-receiver relationship.

Operating Systems

Recent releases

  •  04 Jan 2014 19:00

    Release Notes: This release fixes an authentication problem which posting email from Mac OS 7.1 (the authentication was never successful, the password was never seen). It is also able to define a specific IP as not relayable within a range of relayable IPs.

    •  18 Oct 2013 13:38

      Release Notes: This is mainly a bugfix release, fixing a core dump event in banned/trusted server list generation. It fixes a local MX problem that caused email error rebounces to be lost if the domain was without a secondary MX.

      •  20 Aug 2013 23:51

        Release Notes: This release fixed a problem where the number of "checker" processes within the configuration file was not used. This caused slow email processing if the number of incoming email binding was set to a high value (with over 100 emails received at the same time). All "checker" process were too busy making sure that received emails were good. The number of checkers must be roughly one for every ten incoming channels. Statistics for received, rejected, and quarantined emails were improved and can be displayed by site, group, domain, or user, and as pie charts.

        •  16 Jul 2013 15:20

          Release Notes: This release fixes a problem with user authentication when the remote link for the user group was set to be POP3S over a SSL link, and provides better guidelines to download the application.

          •  08 Jul 2013 14:15

            Release Notes: This is a small improvement release. It is compatible with Fedora 18 and its systemd init process. User-selected display setup (log page size) is now kept within all clement display part. A MySQL cron process impairing the spam detection learning process has been fixed.


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