DKIM-Verify is a software application that can provide DKIM verification for non-DKIM-aware MDAs. Using DKIM-Verify, which functions as a "wrapper" for the MDA, mail originating from and destined for the local domain can be verified. In addition, DKIM-Verify can integrate with mailing list software to provide verification of messages received for later distribution.
SSA Fetchmail is a multi-threaded solution that retrieves new emails from ISP email accounts and forwards them through different channels like email, SMS, or a local SQL repository. It supports IMAP4, POP3, SSL, SMTP TLS delivery, SMPP SMS delivery, and local delivery. SSA Fetchmail supports thousands of email accounts provisioned in a MySQL database. Its performance is better than other solutions.
Scalix Virtual Appliance includes a full installation of the popular email collaboration software Scalix. The only two applications installed in addition to Scalix and its required components are Joe (a simple text editor) and VMware Tools. This appliance should work with any recent version of VMware.
Open-Xchange Virtual Appliance is a virtual appliance/machine that includes a full installation of the popular email collaboration software Open-Xchange. In addition to Open-Xchange, it includes Dovecot, since Open-Xchange is not bundled with any IMAP or POP3 server. It also includes Joe (a simple text editor) and VMware Tools. The appliance was installed using Open-Xchange official guidelines.
Masqmail is an MTA (mail transport agent) for notebooks, workstations, home servers, and generally any host with no permanent network connection. It has special support for multiple transfer routes (e.g. to different mail providers). Address rewriting can be done in several ways. It is a slim replacement for full-blown MTAs such as sendmail, exim, qmail, or postfix and for the intended uses, configuration is much simpler.
OpenSMTPD is an RFC compliant, secure, and simple SMTP server ported from OpenBSD to Linux. It supports the SMTP protocol, including SSL versions for added security, virtual domains, forward files, and external delivery agents like procmail, and can do most of the basic things that other MTA implementations do.
Sendooway is a multi-user and multi-target ESMTP proxy that acts as mail transfer agent. Instead of configuring SMTP servers and authentication data for every mail identity on every device, it allows you to configure them centrally. Sendooway automatically uses the correct smarthost, logs on with the user's account data, and sends their mail.