When a reply is made to a comment the user has left on the blog, an e-mail shall be sent to the user to notify him of the reply. This will allow the users to follow up the comment and expand the conversation if desired.
Detail information: http://theme10.com/comment-reply-notification/
This has been my most loved plugins and for years I had no problems. Until today. Commenters got a fatal error message when attempting to leave a comment. This plugin was the cause. I'm sorry to leave but I'm switching to a different plugin for emailing commenters on my blog.
I use it and very happy with it. Also works with WPML so that I can translate it into other languages.
1.4 2010-10-13 tk (by thomas) : the e-mails are now sent even when the reply is posted from dashboard
1.2 2009-02-18 fix the problem with WP 2.7 paged comments.
1.0 2008-12-19 inition version