Zimbra is the most capable open source email and collaboration suite available today. It provides support for Email, Shared calendar, Document management, Pop3, Address book and lot more. Mails could be tagged and search support is also provided. Zimbra is considered as an alternative to Microsoft Exchange Server.

Zimbra - Email and Collaboration Suite

The JavaMail API is a set of abstract APIs that model a mail system. The API provides a platform independent and protocol independent framework to build Java technology based email client applications. The JavaMail API provides facilities for reading and sending email. Service providers implement particular protocols. Several service providers are included with the JavaMail API package; others are available separately. 
 
The JavaMail reference implementation jar file, includes SMTP, IMAP, and POP3 protocol providers.

The JavaMail API is a set of abstract APIs that model a mail system. The API provides a platform independent and protocol independent framework to build Java technology based email client applications. The JavaMail API provides facilities for reading and sending email. Service providers implement particular protocols. Several service providers are included with the JavaMail API package; others are available separately. 

JavaMail - Java library to build Mail and Messaging Applications

James (a.k.a Java Apache Mail Enterprise Server) is a 100% pure Java SMTP and POP3 Mail server, and NNTP News server designed to be a complete and portable enterprise mail/messaging engine solution based on currently available open messaging protocols. 
 <ul><li>Is 100% pure java capable of running on Java 1.4 onwards</li>
<li>Integrates protocols
 <ul><li>Email
 <ul><li><a href="http://james.apache.org/server/rfclist/smtp/rfc0821.txt" class="externalLink"><abbr title="Simple Mail Transport Protocol">SMTP</abbr></a></li>
<li><a href="http://james.apache.org/server/rfclist/pop3/rfc1725.txt" class="externalLink"><abbr title="Post Office Protocol">POP3</abbr></a><ul><li>Outgoing server</li>
<li>Incoming from POP3 accounts (FetchMail)</li>
</ul>
</li>
<li><a href="http://james.apache.org/server/rfclist/imap4/rfc2060.txt" class="externalLink"><abbr title="Internet Message Access Protocol">IMAP</abbr></a> (James 3)
 <ul><li>Server</li>
<li><a href="http://james.apache.org/jsieve" class="externalLink">Sieve</a> 
 filtering into IMAP mailboxes for incoming mail</li>
</ul>
</li>
</ul>
</li>
</ul>
<ul><li><a href="http://james.apache.org/server/rfclist/nntp/rfc0977.txt" class="externalLink"><abbr title="Network News Transfer Protocol">NNTP</abbr></a> (better known as news)</li>
</ul>
</li>
<li>Is based on open standards</li>
<li>Is a mailet container. Processing is delegated to independent, extensible, pluggable agents
 specified by the <a href="http://james.apache.org/mailet/api" class="externalLink">Mailet API</a>. Any function
 which is not already available (from <a href="http://james.apache.org/mailet" class="externalLink">James</a>
 or from a third party) can be developed.</li>
<li>Is a modular, component based <a href="http://dbpedia.org/resource/Inversion_of_control" class="externalLink">IoC</a> 
 mail platform
 <ul><li>Based on mature, production proved <a href="http://excalibur.apache.org" class="externalLink">Apache Excalibur</a>
 components</li>
<li>James 2 (production) uses the <a href="http://avalon.apache.org" class="externalLink">Avalon</a> framework. Avalon development
 has now stopped but the framework is mature, stable and of proved production quality.</li>
<li><a href="http://james.apache.org/server/head" class="externalLink">James 3</a> (development) supports Spring and is moving
 towards OSGI</li>
</ul>
</li>
<li>Support to create mailing list </li>

</ul>

James (a.k.a Java Apache Mail Enterprise Server) is a 100% pure Java SMTP and POP3 Mail server, and NNTP News server designed to be a complete and portable enterprise mail/messaging engine solution based on currently available open messaging protocols.

James - Enterprise Mail Server

Mireka is a mail server with SMTP, Mail Submission and POP3 services. It is also an SMTP proxy. As a proxy, it can help to prevent or diagnose mail problems, like outgoing backscatter spam. 
 
<ul>
<li>detailed logging</li>
<li>basic mail traffic statistics</li>
<li>filtering by DNSBL</li>
<li>filtering by SPF</li>
<li>accepting mail only for local domains and recipients</li>
<li>wildcards (regular expressions) can be used to specify local recipients</li>
<li>basic tarpit, to prevent e-mail address harvesting</li>
<li>loop detection</li>
<li>configurable maximum message size</li>
<li>easy implementation and installation of custom filters written in Java</li>
<li>separate Message Transfer Agent and Message Submission Agent ports: 25 and 587 by default</li>
<li>proxy functionality for incoming mails (both MSA and MTA)</li>
<li>the proxy can select from more than one backend server, based on the recipient</li>
<li>standalone (non-proxy) Message Submission Agent implementation with file system based mail queues</li>
<li>submission port authentication by IP address or by username-password pair through SMTP authentication</li>
<li>POP3 service for retrieving mail, file system based mail store</li>
<li>aliases, forward lists and (very) simple mail lists</li>
<li>Sender Rewriting Scheme (SRS) for SPF compatible forwarding</li>
<li>secure communication using STARTTLS on all services</li>
<li>"delayed" DSN reports on temporary failures</li>
<li>embeddable</li>
</ul>

Mireka is a mail server with SMTP, Mail Submission and POP3 services. It is also an SMTP proxy. As a proxy, it can help to prevent or diagnose mail problems, like outgoing backscatter spam. 

Mireka - Mail server and SMTP proxy

JES is a multi-featured hybrid MTA/MDA server written in the java programming language. It supports TLS, SSL, SMTP authentication, spam control and lot more. 

Java Email Server

Simple Java Mail is the simplest to use lightweight mailing library for Java, while being able to send complex emails including authenticated socks proxy(!), attachments, embedded images, custom headers and properties, robust address validation, build pattern and even DKIM signing and external configuration files with property overriding, Spring support and Email conversion tools. Just send your emails without dealing with RFC's.

Simple Java Mail - Simple API, Complex Emails (JavaMail smtp wrapper)

Baton is a simple proxy which accepts SMTP connections and routes them to one or more backend SMTP servers based on the envelope sender or recipients. The conversation is proxied in realtime without storing the mail content. There are no downloads but the code works - it is simple enough to be self-explanatory, especially with the test cases. Code derived from this project is used to implement the "fallback host" feature of the SubEtha mailing list server.

Baton - Simple SMTP proxy which routes the conversation to one or more backend servers

CRSMail a 100% JAVA based E-Mail server. It supports SMTP, POP3, Plugins, Can listen on multiple ports, Log's everything to a log file etc.

CRSMail - JAVA based E-Mail server

SubEtha SMTP is a Java library which allows your application to receive SMTP mail with a simple, easy-to-understand API. This component can be used in almost any kind of email processing application. SubEthaSMTP's simple, low-level API is suitable for writing almost any kind of mail-receiving application.
 
It can be used for 
<ul>
<li>A mailing list manager (see SubEthaMail)</li>
<li>A mail server that delivers mail to user inboxes</li>
<li>A mail archiver</li>
<li>An email2fax system</li>
<li>SMTPseudo - A filtering forwarding server</a></li>
<li>Baton - SMTP proxy for one or more backends (rules based on sender/envelope)</li>
<li>Mireka - Mail server and SMTP proxy with detailed logging, statistics and built-in, fail-fast filters</li>
</ul>

SubEtha SMTP is a Java library which allows your application to receive SMTP mail with a simple, easy-to-understand API. This component can be used in almost any kind of email processing application. SubEthaSMTP's simple, low-level API is suitable for writing almost any kind of mail-receiving application.

SubEtha SMTP - Easy-to-use server-side SMTP library for Java

Discover open source projects across all platforms

Projects