spamdyke is a drop-in filter for qmail to provide connection-time blacklisting, graylisting, DNS RBL/RHSBL checking, sender MX checking, improved logging, and more. spamdyke will provide SMTP AUTH and TLS to unpatched qmail servers. Installing spamdyke does not require patching or recompiling qmail.
The QmailToaster is an RPM-based Qmail distribution for CentOS, Fedora, SuSE, and Mandriva. This system is designed for ease of deployment and includes strong anti-spam systems. This includes support for SRS, SPF, DomainKeys, and virtual hosting on the SMTP side. On the user side, this has a Web-based administration interface and supports POP3, POP3 over SSL, IMAP, and IMAP over SSL.
Poprox is a POP3 and SMTP transparent filtering proxy. It does virus scanning using libclamav and is comparable to p3scan in philosophy. Its design is based on a multi-process architecture which allows the detection of libclamav crashes. When this occurs, Poprox is able to delete the offending mail. Debug mode can be toggled by sending a SIGUSR1 signal to the main process. Interactions with users can be translated in any language by using a simple template system.
hermes is a generic, transparent and multi-platform anti-spam SMTP proxy that uses a combination of techniques (like greylisting, throttling, DNS white/blacklisting, SPF, etc.) to stop spam from reaching your mailbox. Many mailboxes see a 98% spam reduction with no false positives, as hermes is not filtering email based on content, but on strict adherence to the SMTP standards. It's also compatible with most SMTP extensions like STARTTLS (for SSL security) and SMTP-AUTH (for user authentication).
Vanguard provides enterprise class anti-virus and anti-spam protection to multiple internal mail servers, including the Gordano Messaging Suite, Microsoft Exchange, and IBM Lotus Notes/Domino. Dual anti virus scanning engines provide both traditional signature based virus protection and advanced Zero Hour protection. Any number of internal servers can be protected from a single Vanguard server. Each of those servers may be servicing the same Internet domain, separate Internet domains, or even multiple Internet domains on a single server. There is no limit to the number of protected domains or message throughput.
a2pdf converts plain (ASCII) text files to documents in the PDF format. Its features include optional line/page numbering, multiple font support, syntax highlighting for Perl source code, and customizable headers and footers. Binaries are available for Linux x86, Mac OS X (Intel), and Microsoft Windows platforms.