I cant say this is news to me, many rip off companies have been doing this for years and as we all know the Cartel have been over the last five years trying to take over every network and client out there, especially the gnutella network because their front companies like "discordia" use that network with many of the old client names obtained after suing the real company to death or stealing websites with legal trickery.
Rest assured you can obtain winmx 2005, winmx2006, winmx2007 etc etc and others called winmx classic, winmx gold, I think you get the picture that they are all either scam sites or fake clients that use another network, if folks are mislead into trying such networks please be aware that out of the folks threatened with a law suit over the last few years many where using the gnutella netork and the majority of the others used kazzaa as both are pretty poor in the security stakes and leave you wide open on all fronts.
Bottom Line
If it doesn't say "frontcode technologies " on the file and has a number higher than 3.54b4 then remove it, and check your machine for spyware,