How it looks:

This plugin adds the 'reply' option to comments. When user hits this option, he is redirected to the comment box. On the top of the box, there's a text informing for which comment the user is answering.

After submitting, the  comment is automatically filled with text:

Reply to: Name of the user

Text of the comment

The commercial version of this plugin adds AJAX-supported threaded comments and forums. You can view it in action on elgg.vazco.eu. (comments and forums)

Installation:

• copy to mod folder and enable