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SPF
Sender Policy Framework
Originally developed by HP as 'OpenMail', SCALIX Server is a Linux based Enterprises Mail and Calendar Server. What differentiates SCALIX Server from other solutions is its MS Outlook plug-in that makes it a compelling alternative to MS Exchange. Outlook users can point their client at a SCALIX Server running on Linux and experience all the features that typically would be available only from MS Exchange. SCALIX Server also supports venerable POP, IMAP, LDAP, Active Directory, and other obligatory interfaces and prototcals. Recently SCALIX released a Web Mail client using the 'AJAX' framework that provides 'fat-client' Outlook-like mail and calendar functionality.  
Elsewhere
Spam Assassin
zap technologies
tablet | printable