now i’m not sure about the security ramifications here .. but if you need something quick and easy this may fit the bill.

JS-Kit is a free service that will add comment functionality to any page you paste it into.

As you might have guessed from the name, it’s a JavaScript solution that automatically fetches the comments for a page from the JS-Kit server when the page loads. Comments are threaded and are posted via Ajax without having to leave or reload the page.