Comment Mention Pro is an addon for wProject that notifies users when you mention them in comments.

To use it simply type the @ symbol and start typing the name of the person you want to notify about the comment, and select their name by either pressing tab or clicking their name with the mouse.
When someone is mentioned in a comment, a notification is pushed to them with a link to the task and comment.

Additionally, any mention of a user in a comment will be linked to their profile page.