Free mua software for linux

GNU Anubis is an SMTP message submission daemon. It represents an intermediate layer between mail user agent (MUA) and mail transport agent (MTA), receiving messages from the MUA, applying to them a set of predefined changes and finally inserting modified messages into an MTA routing network.

The set of changes applied to a message is configurable on a system-wide and per-user basis. The built-in configuration language used for defining sets of changes allows for considerable flexibility and is easily extensible.

parp is a powerful, extensible e-mail filter with sophisticated anti-spam capabilities. Its made as a complete replacement for procmail, is MIME-aware, and acts as a filter, daemon, or on mailboxes.
This was yet another personal itch which needed scratching. I receive between 5 and 20 spam e-mails most days. It wasnt only mildly annoying to have to hit delete more than normal, but I also forward all e-mail which ends up in my main inbox to my mobile (cell) phone via email2sms and an Internet/SMS gateway, and I was sick to death of my phone bleeping a lot through the day purely due to junk mail.
I started looking at all the available anti-spam filters. Over a period of two years, I looked at many, including the NAGS filter, despam, various complex anti-spam procmailrcs, the spamometer, blackmail, filter.plx, zfilter, spamstop, junkfilter ... but various things put me off all of them:
Some werent written in Perl. Call me a Perl bigot, but if there was ever a case of Perl being the right tool for the job, its an e-mail filter. Extensibility and maintainability were very high on my list.
Some were terribly coded. I refuse to put my e-mail at the mercies of bad code (and that includes sendmail ;-).
Some insisted that you use a particular MDA or MUA. I have no intentions of changing from mutt and qmail.
Many filtered on only the headers, or only the body. I want to filter on both, not all the time, but in some circumstances.
None were as accurate as I wanted. My goal was at least 99% accuracy. (At the time of writing, parps accuracy is hovering around the 99.8% mark.)
Main features:
- Can act as a filter in a similar manner to procmail, or directly on files in Mbox format (and possibly other formats via Mail::Box - untested), or as a daemon processing mails from a spool. In the latter case, mails are injected into the queue via a tiny (15k on my system) executable which handles locking correctly.
- Standard filtering actions are available (deliver to mailbox, pipe to command, reject as junk etc.)
- Highly sophisticated spam detection heuristics: currently around 40 different tests performed in a worst case scenario, although all tests optimised for speed (e.g. fast tests performed on headers, then slower tests only performed on body if necessary). N.B. Im considering incorporating the SpamAssassin ruleset at some point too.
- Optional cross-checking with the Open Relay Database.
- Filter adds X-Parp-Accepted: and X-Parp-Rejected: headers so that you can easily monitor its filtering strategy without leaving your mail reader.
- MIME multi-part aware, e.g. will not be confused by binary attachments.
- Berkeley DB format friends database, for keeping false positives to an absolute minimum.
- Automatic extraction of addresses into the friends database from emails which pass the spam tests. Semi-automatic removal of addresses from the friends database on the rare occasions parp gets it wrong. The friends database is also easily editable with my dbm utility.
- Other `grace tests allowing bona fide persons communications through (e.g. passworded e-mails) just in case all the other tests go badly wrong.
- The configuration files are written in raw Perl, so you can extend the filter arbitrarily using the main programs API.
- Comprehensive logging and error-trapping systems.
- Auxiliary program to print out comprehensive statistics on all aspects of filtering (see the sample output).
- Ability to log false positives/negatives when spam detection has gone wrong in a way which can be interpreted by the statistics program to determine the filters current accuracy of spam detection.
- Mostly RFC822-compliant state machine parser of Received headers, enabling extensive spam trace analysis and retaliative action. Read its man page or source if youre curious.
- Duplicate removals (by message id).
- Emails which have already been filtered can be used as regression tests, to easily spot problems when you make changes to your filtering logic.
Version restrictions:
- Limited documentation so far. This is gradually improving.
- Requires some knowledge of Perl / programming. (Ironically, if it didnt, there would be far greater limitations to the filters flexibility.)

Flail is a command-line MUA (mail user agent) written in Perl. Flail project is designed to give you the ability to map little gobs of Perl over your messages and folders, support multiple identites and mailboxes, and integrate cleanly with PGP and GPG.

Flail is not coded very cleanly, and is primarily hackerware: Perl hackers will probably like it, and everyone else probably wont.

libESMTP is an SMTP client which manages posting (or submission of) electronic mail via a preconfigured Mail Transport Agent (MTA).
libESMTP library may be used as part of a Mail User Agent (MUA) or other program that must be able to post electronic mail but where mail functionality is not that programs primary purpose.
The availability of a reliable lightweight thread-safe SMTP client eases the task of coding for software authors thus improving the quality of the resulting code.
Main features:
- libESMTP supports many SMTP extensions, notably PIPELINING (RFC 2920), DSN (RFC 1891) and SASL authentication (RFC 2554). SMTP AUTH is implemented using a SASL client library integrated into libESMTP. Supported SASL mechanisms include CRAM-MD5 and NTLM.
- libESMTP is also efficient. Because it buffers all network traffic, when used in conjunction with a pipelining SMTP server libESMTP significantly increases network performance, especially on slow connections and those with high latency. Even without a pipelining server libESMTP offers significantly better performance than would be expected with a simple client.
- libESMTP is not designed to be used as part of a program that implements a Mail Transport Agent. This is not because the code is unsuitable for use in an MTA, in fact the protocol engine is significantly better than those in many MTAs. Rather, by eliminating the need for MX lookup and next-hop determination, the design of libESMTP is simplified; thus goals are made achievable. Besides, such features are undesirable in a program that is not an MTA, particularly if the client is behind a firewall which blocks access to port 25 on the Internet.
Enhancements:
- This release applies bugfixes and plugs some memory leaks.
- It also attends to a few autoconf-related issues.

DisSent (short for "Distribute Sent Mails") is a program for separating your sent mail from a single folder into different folders based on properties of the individual messages in the folder.
DisSent scans your mail storage and proposes a set of actions to tidy up your sent mail folders.
Almost all mail user agents (MUA, "mail clients") Ive encountered implement a standard way of handling outgoing messages by placing a copy of every sent message into a certain special folder.
While this might be a fail-safe approach, it is not very useful for you if you belong to those people who work with mail folders and rules to sort incoming mails. Usually, youll have your rules setup so that an incoming mail from John Doe will be moved into a separate folder, lets say "INBOX.Friends.JDoe". Now if you reply to this mail, your answer is moved to an entirely different folder, and if you want to look up your answer some time later, youll have to browse through all the mails you sent in the meantime. This is ugly.
Enters DisSent (short for "Distribute Sent Mails"). DisSent scans your mail storage and proposes a set of actions to tidy up your sent mail folders. More precisely, it gives you a list of messages along with proposals on where to move these messages. You can then select the mails you want to move and let DisSent do the actual work.
Known Issues
- The progress monitors should be modal so you cant execute other actions while DisSent is busy.
- The protocol SMTP in the login window doesnt really make sense.