Wow.. embarrassed to admit that I didn't know what this was. For any one else, here's the short description.
Suhosin (pronounced 'su-ho-shin') is an advanced protection system for PHP installations. It was designed to protect servers and users from known and unknown flaws in PHP applications and the PHP core. Suhosin comes in two independent parts, that can be used separately or in combination.
So now my next challenge is to figure out how to find out if my Host vendor has it installed.