Is there a spam filter that works with ISPConfig that allows a user to block a specific type of content (ie. all pornography, etc.)? I've seen an ISP that developed its own software that does this and it does a great job. I imagine because it's easier to block a specific type of content.
I'am not aware of such a software. But you might do this by adding specific rule sets to the spamassassin which is integrated in ISPConfig.
Take a look here: http://www.rulesemporium.com/ http://wiki.apache.org/spamassassin/CustomRulesets http://www.askdavetaylor.com/how_do_i_add_custom_spamassassin_rules_for_content_filtering.html ISPConfig's SpamAssassin is located in /home/admispconfig/ispconfig/tools/spamassassin.
Or... Have a look here: http://std.dkuug.dk/keld/virus/header_checks It's for virus header warnings, but you will get the point how to modify it for "spam text" headers. You can do the same for body text: http://std.dkuug.dk/keld/virus/body_checks