Subscribe to "category" for email notifications

Within the ACP, if I set "Enable active topics" to YES for my "categories" (I have four categories, with a few forums in each category), then a "subscribe to forum" option will appear on the front-end on the category page (otherwise, the option isn't there). When I subscribe on the category page the system generates the usual message ("You have subscribed to be notified of new posts in this forum"), but I notice that the system does not actually subscribe me to any of the forums within the category. As such, I don't actually receive any notifications of new posts within that category (i.e. of new posts to the forums within that category).

I suspect either (1) the system shouldn't give the user the option to subscribe to a category, or (2) it should give the option, but it ought to subscribe the user to all the forums within the category so that the user actually receives notifications of new messages within the category.

Since it goes "Category --> Forum --> Topics --> Post" it is useful to be able to subscribe to a category in order to be notified of all the posts within all the topics of all the forums within that category. So when the user subscribes to a category, the system should say something like "Are you sure you would like to be notified of all the posts within all the forums within this category" and the system should warn the user that it would override any individual subscription settings they had previously for the forums/topics within that category.