Riq, I know you disabled this feature, but I suppose many of us find it very useful. I have few topics in which I expect some real problems solutions, so it's good to know when something happens there...
What kind of problems you had with this feature? Is it about the traffic all those emails are generating or what? If it's about the traffic maybe we can get some better solution, like private messages inside the forum, so your site doesn't need to send all those emails...
Thanks
Edit: I just saw there is a RSS feed dedicated to this. Is this actually working or you disabled that also?
Edit2: Well RSS feeds works very nice, so it's better method anyway...