MyBB Community Forums

i want to notify users whenever there is a new reply to the thread they have already replied to.
in other words,
i want the users to be automatically subscribed to the thread they have replied to.
how can i achieve this?

Not for 1.8. but I know for 1.6.x this works.
http://community.mybb.com/thread-126455-...#pid915130

Perhaps someone who is more knowledgeable can build off of that.