Apple Mac OS X Server Ver 10.4 - Manual (Page 18)

18 Technology Overview
Mac OS X Server
Post x and Cyrus are easy to con gure and manage using the Server Admin utility.
Protection against junk mail and viruses
To defend your servers and clients against unwanted mail and destructive viruses,
Mac OS X Server v10.4 integrates two popular open source projects: SpamAssassin
for adaptive junk mail  ltering and ClamAV for virus detection and quarantine.
SpamAssassin enables Mac OS X Server to analyze the content of each mail message.
Using a wide variety of local and network tests, SpamAssassin assigns a probability
rating that the mail is spam. If the probability is high, it classi es the mail as potential
junk mail and allows the user to decide how to handle it. The SpamAssassin junk mail
 lter is adaptive, which means it can be trained to recognize which marginal mail mes-
sages are spam and which are not. Training can be done automatically: SpamAssassin
analyzes the content of user inboxes every night and adapts its  lters accordingly. Or,
for greater control, postmasters and users may prefer to train SpamAssassin manually.