Twisted is an event-based framework for Internet applications. It includes a Web server, an SMTP/POP3 server, a telnet server, an SSH server, an IRC server, a DNS server, a generic client/server pair for remote object access (Perspective Broker), and APIs for creating new protocols. It supports integration with GTK+, GTK+ 2, Qt, Tkinter, wxPython, Mac OS X (PyObjC) and Win32 event loops. It also supports TCP, SSL and TLS, UDP, Unix sockets, multicast, and serial ports. Supported protocols include HTTP, FTP, SMTP, POP3, IMAP, TOC, OSCAR (AIM and ICQ), SSH, DNS, IRC, NNTP, Jabber, SOCKSv4, Telnet, SIP (for VoIP), and XML-RPC and SOAP using external packages. Most protocols are supported as both servers and clients.
qpsmtpd is a flexible smtpd daemon written in Perl. Apart from the core SMTP features, all functionality is implemented in small "extension plugins" using the easy-to-use object oriented plugin API. qpsmtpd was originally written as a drop-in qmail-smtpd replacement, but now it also includes an smtp forward and a postfix "backend".
libtld is a library used to extract the TLD from a URI and to check email validity. This allows you to extract the exact domain name, sub-domains, and all the TLD (top level, second level, third level, etc.). The problem with TLDs is that you cannot know where the domain starts. Some domains can use one top-level domain, others use two, etc. However, it may be useful to know where the domain is to have the exact list of sub-domains. For example, if you want to force www. at the start of the domain name if no other sub-domains are specified, then you need to know exactly how many TLD are defined in a URI. The libtld offers one main function: tld(), which gives you a way to extract the TLD from any URI. The result is the offset where the TLD starts. This gives you enough information to extract everything else you need. For emails, the library is capable of parsing a string that represents a list of email addresses to be verified. The verification includes a check of the domain name and its TLD.
stdnoj is a cross-platform C++ class library that includes classes for using portable strings, databases, SMTP, POP, NNTP, arrays, files, directories, logging, email, and sockets. While templates are used, no reliance upon STL or other (traditionally error-prone) technologies has been used, which increases portability between compilers.
Liferay is an enterprise portal. It handles users and portlet drawing, has a full administrative interface, supports all the major databases and the main J2EE application servers, and has single sign-on capabilities and multiple language support. It uses Apache Lucene for document searching. A number of portlets are included, including a guestbook, a calendar, a mapping utility which uses Expedia, news, polls, a document library, and live stock information.
Twisted Mail provides client and server implementations of SMTP, POP3, and IMAP4. These differentiate themselves from the Python standard library implementations both by presenting a much higher-level, easy-to-use interface and in their server components, which allow the implementation of custom servers for each protocol without dealing with protocol-level issues. Twisted Mail includes a simple demonstration email server which accepts messages over SMTP, stores them in a Maildir arrangement, and can serve them to clients over POP3.
MailSpammer is a simple mailing list manager for smaller e-mail lists, using procmail and Perl. MailSpammer does not require administrator access, aside from initial setup (creating e-mail aliases), and features subscription, unsubscription, moderation, and archiving. The goal is not to be a majordomo-alike mailing list manager, but instead to provide a lightweight way to handle basic list management tasks.