I am looking for a content management and review and rating script to integrate into my existing directory. I want to allow users to register to the site, and have a admin area where they can add and view listings to their favorites and rate and leave reviews for listings. I also am looking for a private message board to incorporate into the site to allow owner of listings and users to communicate through. Does any one know of any prebuilt scripts that can be easily integrated into my existing site? The current directory is php/mysql based.