XF 1.5 Filter new signups by email domain?


Is there a way to block a certain domain from registering on my forum? I'm getting a lot of spam from one certain domain and while I've turned on most of the spam tools I can find, there are clearly real people behind these and they keep getting around whatever I do.

But, they all come from the same domain so if I could block that domain and whatever the next domain is that pops up like this, it would make it much easier.