Microsoft Exchange compatible server and client libraries
OpenChange is a portable Open Source implementation of Microsoft Exchange server and Exchange protocols. It provides a complete solution to interoperate with Microsoft Outlook clients or Microsoft Exchange servers. OpenChange client-side library is used in existing messaging clients and is the solution in new projects to communicate natively with Microsoft Exchange and Exchange-compatible servers. OpenChange server is a transparent Microsoft Exchange server replacement using native Exchange protocols and does not require any plugin installation in Outlook.
Email2Fax and Fax2Email gateway for Asterisk, that could be integrated to your own existing Asterisk.
Send emails quickly and efficiently.
FalconMailer is a Java-based Mail API that can send emails quickly and efficiently. The API is easy to use and is much faster than the JavaMail. FalconMailer uses SSL.
Your own mailing system (most easiest to use with zero configuration) for the entire world (available in almost all the languages of the world) which will include Mail User Agent and Mail Transfer Agent thus trying to give maximum speed while transferrin