SRO can't do anything about it, they rent the servers.  So why mail Joymax at
    Joymax co.,Ltd
    78, 13F West IT Venture Bldg Garakbon-dong Songpa-gu
    SEOUL,  138803
    KR 
or contact their website administrator at 
sonkilmer@joymax.com (PHONE) +82-2-420-8854
when you can complain to their host 

 unfortunately, I'm not entirely sure who that is.  I'm too lazy to look through my router's activity log to see what their game server's IP's are but if anyone knows them, I can very easily tell those guys to get their network back in shape so US companies don't have to ban them.