If you don't mind blocking all users of a particular Ukranian ISP, then you can block the entire 217.198 IP range. This ISP, or rather its users, is the cause of most of the comment spam I get, so hopefully blocking it entirely will stop that. Apologies in advance to anyone who uses this ISP but then maybe you need to write to them and tell them not to be as tolerant to spammers.
Beware of Ukranian spammers
