I advise my users to never reply to spam, doing so proves the address is valid and messages read which will encourage the spammers to send even more crap. I tried content filtering to deal with spam in the past but do not at all these days because false positives are not acceptable to me. If my mail server accepts a message it always gets delivered to a mailbox and never to /dev/null.
The only effective way I have found of dealing with spam is to add the mail servers they use to relay their trash to an IP blacklist and reject future messages from those servers. That means some legitimate mail will bounce, but that is acceptable because those senders are notified of the delivery issue and can try to send again using a less shady service provider.
The only effective way I have found of dealing with spam is to add the mail servers they use to relay their trash to an IP blacklist and reject future messages from those servers. That means some legitimate mail will bounce, but that is acceptable because those senders are notified of the delivery issue and can try to send again using a less shady service provider.