How to restrict comment-ability on a per-user/per-page basis?

Hi there!

I sure could help a push into the right direction.

Is there a plugin that allows me to restrict a specific subscribed user to comment on a specific page only?

I want to be able to create something like a personal 1-on-1 chat page that only me and a specific user can comment on, while everyone else can only read but not comment on that page.

Also (probably my real problem), it has to be scalable… meaning, I need to have this functionality for multiple users, each having “enhanced” access to their own, personal page where only they (and me, the admin) can comment.

I would work with password-restricted pages, but I want the world to be able to read all those pages… I just need to be able to restrict comment-ability on a per-user basis.

I’ve been thinking about using a custom field with the user’s nickname or something and a PHP “if” function to show the comment-posting form only when the nickname fits the page’s custom field.

Yet, after about 40 hours or shoving code and pixels, my brain just produces fruit-salad instead of a bright idea with a short code-snippet.

Anyone? Please? Pretty Please? ??