Simeon was an IMAP4 email client by The Esys Corporation. It was one of the first clients to support IMSP, along with Mulberry. It also supported MIME and Kerberos authentication.
Simeon was available for several platforms, including Windows, Mac OS, and X/Motif workstations, and it provided a similar look and feel on each system.
Simeon was the default email client installed on Heriot-Watt University's IT infrastructure.[1]