I'm rather curious as to why you'd be okay with people using proxy servers, especially given these are usually used for illegal purposes rather than legit ones?
/edit
The first IP is listed in 6 blacklists, and ProjectHoneyPot has it listed as a comment spammer;
http://temerc.com/Check_Spammers/?ip=195.7.100.44
The second is listed in even more blacklists;
http://temerc.com/Check_Spammers/?ip=200.65.127.161
Well, are there any legit and free proxy servers on the internet? I totally understand that people choose to use any proxy server they find, as long as they don't pay. As you probably know, there are web sites where you can find lists of proxy servers, and where owners are sometimes unaware of that their proxy server is misconfigured, and thus letting the people outside their network use it. The fact that this user found a proxy server that was also used by spammers is just a coincidence.
As to letting people use a proxy server when they access my forum: As I have written before, the discussion forum I manage is based on anonymity. In fact, nobody registers and discloses their real names. That's a principle that is very common at some discussion forums in Sweden (I could give you some URLs here, but the forums I'm talking about is all in Swedish). Some people might be logging in from their offices, and maybe they don't want their work places to be disclosed in any way (as reverse host-lookups might reveal the domain name, and thus the work place), and that's totally OK for me.
Don't get me wrong, the anonymity is NOT because the discussion forum is a place for discussions on illegal activities. We discuss many things, from our political views to our sex lifes. But not everybody is willing to admit stuff they talk about if their identity is known in some way, maybe it has to do with that they think that their point-of-view won't be accepted by the majority of users. In many cases, people have used proxy servers to register, and then went over to using their own ip addresses after they have gotten to know the members of the discussion forum better, and realized that their point-of-view is in fact OK to reveal. So I have to be somewhat tolerant when it comes to usage of proxys in order to encourage people to register.
Until now two users among over hundreds of spammers were legit, so the botScout API has helped me a lot. But non of the spammers used a Swedish nickname during their attempts, like in this case (the word "Apskaft" is a Swedish word, meaning "Ape-headed" or "One with an ape as an origin").