What happens is that MailScanner will tag the emails, modifying the subject line with, for example, ***SPAM***. You can configure it to add whatever you want in the subject line by modifying the option in the MailScanner.conf file. It will then either store, deliver or delete the message according to how you setup it up.
I had my users setup a spam folder and a rule to move all emails tagged with ***SPAM*** to it. That way, they can sort through it on their own.
MailScanner, with the correct settings, will quarantine all emails, ham or spam, which can be released if tagged incorrectly. I've implemented MailWatch on my setup to do just that.
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