From the article:<p>Our leading theory is that the Great Firewall inside China is manipulating DNS responses due to blacklisted or blocked keywords. This affects any system that has to pass through the Great Firewall before it reaches the end-user/client. Most of the keywords relate to VPN software, proxies, adult sites, file and text sharing and torrents. This is consistent with the kinds of material that China is known to censor within its borders.