Does anyone know of a distributed spam filtering application that is Plesk friendly? Our SPAM problem is just out of control. SpamAssassian is catching almost nothing recently and I'm getting many complaints from my users who are reporting upwards of 200 SPAM messages a day. I've put my PC users on Cloudmark SaftyBar and that solved the problem entirely. However half of our company is on Macs and I'm not aware of a similar program available for Macs. So I'm looking for alternatives. Any ideas are appreciated.