Open Source Mac Mail Transfer Agents

E-MailRelay is a simple SMTP proxy and relay MTA, written in C++, for Linux and Windows. As a proxy all messages can be passed through a user-defined program, such as a spam-filter, which can drop, readdress, or edit messages as they pass through.

mailsend is a simple command line program to send mail via SMTP protocol. It can send a piece of alert mail from a program in a networked Windows machine. It's feature-filled, cross-platform, free and open source, and does not use any config file.

YPOPs! is an application which emulates a POP3/SMTP mail server and provides free POP3 and SMTP access to Yahoo! Mail. It does not depend on Yahoo's POP3/SMTP mail server. You can use a mail client of your choice!

ZMail allows you to send email from anyone, to anyone. You can use ZMail to send fake or anonymous emails. Have fun!

iMailist is a software allowing the sending of mails to format HTML to a whole mailing-list. The program is written in Objective-C/Cocoa and works on Mac OS 10.3

Jamm (Java Mail Manager) is a web application to manage virtual email account information stored in an LDAP directory. It is meant as an administration tool for sites using mail servers, such as Postfix and Courier-IMAP.

GreenMail is an intuitive and easy-to-use test suite of email servers for testing purposes. Supports SMTP, POP3, IMAP with SSL socket support, and configurable user accounts and credentials. All in 100% Java. WE'VE MOVED TO GIT HUB: https://github.com/greenmail-mail-test/greenmail

jwSMTP, Send email programmatically (C++ code/lib). Linux, BSD, Windows etc. Attachments, Multiple recipients, Cc/Bcc recipients supported. MX lookup or send to an SMTP server direct. LOGIN and PLAIN authentication now supported. Html or plain text forma

NMail provides an SMTP client & server along with an IMAP4 server; all are written in C#.

GITST Email Sender allows you to send multiple emails from multiple email accounts adding limits on each email account For example, you want to send 500 from gmail then switch to yandex and send 300 from yandex and so on that is all what it does sends unlimited emails from multiple different email accounts it is basics of anti-spam penetration system

This project builds on top of the (and adds additional) scripts included with msmtp (a command-line send only email client) in order for it to act as a queueing Mail Transport Agent (by acting as the sendmail command; it also offer an minimalist SMTP server mode) with some additional features like verify-before-send (which requires you to confirm that you really do want to send email, after a required delay (cooling off period)) for those who need to think twice about the wisdom of what they send, or who tend to notice their grammar spelling errors after the fact.

This java program allows you to make backups of your emails from one server to an other by copying emails over IMAP. It can also be used to switch emails you have from your old provider to your new one.

The goal of this project is to develop a very simple SMTP server that responds to SMTP requests and makes received messages available for query at a later time. All useful features for a SMTP server that can be used in an automated testing suite.

DKIM for JavaMail is a small JAR that can be easily implemented in existing Java projects using JavaMail for sending DKIM signed emails.

Foedus Mail is a mail server written in Java. The goal is to produce stable IMAP, SMTP, and POP3 support and then to build upon and refine it.

JMultiSend is a simple and fast solution to send mass emails (Bulk E-mail); it only needs to load the list of addresses, the message (HTML or TXT), the data and then send. It is possible also to manage mailing lists subscribtions simply by emails, to send personalized messages with the user name and to schedule delays up to 24h (86400 secs); all this also from command-line. Since it is developed in Java it is a cross-platform application and does not need installation but needs only the Java Virtual Machine (version 6 or higher) that, in the case, is very easy to download and install.

LIMeTool (pronounced like the fruit), is intended to be a simple and easy interface for managing accounts on an integrated Sendmail/LDAP/Cyrus IMAP installation. It's written in PHP and is realitively easy to configure and expand.

Pure Perl implementation of the Milter protocol used by Sendmail, including drop-in replacement for the Sendmail::Milter interface.

PyWebMail is a Python library and POP3 gateway that enable working with WebMail servers like with POP3 or IMAP mail server. Currently Mail.Com, Yahoo! Mail, Gmail, Netscape.Net, HotMail and some minor servers support is finished.

smtptrapd is a multi-threaded daemon written in C that provides a RFC 2821 compliant SMTP service that always returns a 4xx soft error to the RCPT TO verb. It can be deployed as a secondary MX to reduce the amount of inbound spam.

The OpenPEC project is a collaborative effort to develop an Open Source Certified E-Mail System (in italian: Posta Elettronica Certificata or PEC) as requided by the Italian law. See the DigitPA (CNIPA) site for details (http://www.cnipa.gov.it)

This anonymous emailer script written in PHP is a free, opensource project designed to send EMails from anyone to anyone, with additional details such as Reply-To ,an anti-spam CAPTCHA and a WYSIWYG.

Anti-Bot Form Mailer is a PHP script that helps webmasters reducing spam received via their contact or support form.

A SMTP-Proxy that allows authenticated SMTP sessions to traverse, while stopping SMTP sessions from internet worms and SPAM bots. It can also be used transparently so clients need no additional settings, just auth. to their freemail of choice.

Email2Fax and Fax2Email gateway for Asterisk, that could be integrated to your own existing Asterisk.