Collax Groupware Suite is a complete collaboration, e-mail, and messaging server with Outlook MAPI support. It offers enterprise email server functions, anti-spam and anti-virus filters, GUI management, a file server for SMB, NFS, FTP, and Apple shares, backup/restore server, IM server, and fax and SMS server. The groupware offers AJAX Web mail, calendar, team calendar, contacts, and tasks, and supports ActiveSync for mobile devices. It is free for private or commercial use of up to five users.
Collax Business Server is an all-in-one Linux server for small- and medium-sized businesses. It delivers all the important network services within a heterogeneous business environment for communication, infrastructure, compliance, groupware, and storage, all in a reliable and secure way which is easy to manage. It also provides essential security functions such as firewalling and virus and spam filtering, to protect against hacker attacks, viruses, and unsolicited email messages.
zmaildrop is a mail delivery agent (MDA) specifically designed to analyze emails, extract relevant information, and send it to a Zabbix server. It is designed for use with schedulers, backup tools, and security monitoring tools that report information via email. As an MDA, it integrates easily with mail transfer agents (MTA) such as Postfix, Exim, and Qmail, or mail retrieving tools as Fetchmail. It is highly configurable, using a simple YAML syntax to describe tool-specific mail formats.
Pymailheaders is a small GTK+ program which displays mail headers in your mail box. It is an innovation of xmailheaders, with a few more handy features like new mail highlighting, multi-language support, lauching regardless of network connection status, and auto-reconnecting. IMAP4 and POP3 protocols and XML feeds (including Gmail) are supported.
Xplico is an IP traffic decoder that extracts data from an Internet traffic capture. From a pcap file, it can extracts each email (POP, IMAP, and SMTP protocols), all HTTP content, VoIP calls (SIP, RTP, H323, MEGACO, MGCP), IRC, MSN, and so on. It isn't a packet sniffer or a network protocol analyzer, but rather an IP/Internet traffic decoder or network forensic analysis tool (NFAT).
fakehermes is a small, lightweight fake SMTP server. It's useful as a way to avoid spam by configuring your domains to point their secondary SMTP server to a fakehermes server. It will log not only the email messages involved, but also how they are trying to send email and whether they should be considered spam or not. This information can be used to "profile" the spammers that send you spam and can allow you to configure or tune other spam filters. It supports SPF and RBL checking.
SeeYouLater's purpose is to fetch a list of IPs of known spammers and to ban them by putting them in /etc/hosts.deny. /etc/hosts.deny is usually read by xinetd or daemons using tcpwrapper. The software is composed of: the feeder, that looks at SMTP daemon logs for the string ++BAN:IP++ and feeds the database accordindly; and the butcher, that looks at the database and updates /etc/hosts.deny. You may want to run the butcher on a system that has no access to the SMTP logfiles, but you can install both packages on the same system. It has been written to run with Exim.