Comment moderation and notification

Anyone have any advice for the best way to tackle this?

A user has a post on the site and a site visitor comments on it.

I need the comment notifications to work like so:

1. site visitor posts a comment.
2. comment is held for moderation but only the admin (me) is notified via email.
3. The admin approves or deletes the comment.
4. If approved, a new comment notification email is sent to the post owner.

Cheers,
Geary