A pure-perl simple AV engine. Not that fast, imperfect detection, but really great for simply filtering mail without all the hassle of installing some AV application. And, the author works tirelessly to keep it updated.
Mail15 are a company well known for spamming. I've personally recieved over 3000 messages over the last two days as they've dictionary attacked my mail server, advertising their service.
Any module that promotes a spamming outfit such as this one deserves utter contempt, as is reflected in my rating. A module that has a direct negative effect on how much money I have to spend by helping those who are increasing my bandwidth bill with their spam should not be on the CPAN.