simple spam filtering for AMS?

Hey all, Any of you who administer mail servers know that the primary user request is "please get these junk messages away from me!" I'm a Mac consultant and recently began administering my first OS X Server box, and I didn't even get out of the initial interview before the client made the above request. I've read on afp548.com all about setting up alternative Mail Transfer Agents like Exim; installing Spamassassin; etc. However, I'm loathe to use these methods because they're so command-line heavy, for three reasons: 1. I'm concerned that installing UNIX-based applications will lead to hell every time I upgrade or update my OS X Server version. 2. I feel a responsibility to make my clients' server configurations as Mac-admin-friendly as possible. I won't be their consultant forever, and they shouldn't have to pay the next guy to go through a command-line jungle of my making. Most Mac admins don't know UNIX admin that well, and I don't want to set up my clients' boxes with the assumption that we do or will. 3. I don't really want to become a UNIX sysadmin in this lifetime (maybe the next one). I don't mind using the command line every now and then, but I prefer that my server resources not be half-hidden in command line processes. If I wanted to learn UNIX that bad, I'd just scrap the Macintosh and install Linux. It's not that I refuse to install any apps via the Terminal; I will happily do so IF they won't break every time the system gets upgraded, and will require minimal admin hassle, such that I could leave simple instructions for my successor. So, all that said, what are my (possibly limited?) options? Many thanks and keep up the great work-- Noam