1)   602LAN SUITE 5.0.08.0403
Secure messaging solution with web collaboration contains SMTP/IMAP/POP3/LDAP services along with integrated anti-virus and advanced anti-spam protection. Native Outlook support provides synchronization of mail, contacts, tasks, and calendar items.
groupware, collaboration, messaging, email, e-mail, mail, fax, task, calendar, contacts,

 2)   ORF Enterprise Edition 2.1
ORF Enterprise Edition is an enterprise-level anti-spam solution that helps you to block spam before it reaches your network. ORF uses a combination of anti-spam technologies to stop the spam on SMTP protocol level.
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 3)   SpamSquash 2.0.1
SpamSquash is a spam filter that uses two methods for filtering, a Bayesian filter and DNS black lists. It's used with a third party pop3 email client, such as MS Outlook and Pegasus Mail. It also includes white and black lists. Gets over 99%.
spam filter, email filter, bayesian filter, pop3 filter, SpamSquash, email, dnsbl, outlook, pegasus, spam,

 4)   mxORB 2.2.3
mxORB is a server-side spam filter that consistently blocks over 98% of unsolicited commercial email (also known as spam) at a fraction of the cost of other filtering solutions.
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