Don't worry that you are getting notification, they have many many ip's, they are getting redirected before your forum, thread or post that they request loads, you get notofication of the thread they attempted to call.
So in a nutshell Victor, the mods working great, relax and worry not
Edit: You don't need to use the full UA to ban them, you can simpy use Baidu in the list and that will do the trick, using the full UA means you are only banning anything that visitis with that entire UA so if they use one thats slightly different they'll get through but using just Baidu will trap them all!