Currently I know little about this service but I learned of this Chinese email service at http://www.idnforums.com/forums/36176-idn-email-server-and-client.html

The company offering EAI is https://栖安.中国

Registration of an EAI is at https://栖安.中国/register.php?_language=zh_CN or https://栖安.中国/register.php?_language=en_GB

login is at https://函.中国 or https://函.中国/?_language=en_GB or https://函.中国/?_language=ko_KR or https://函.中国/?_language=pl_PL or https://函.中国/?_language=th_TH ...etc... Just choose your preferred language for the login dialogue. I think this is a rather impressive feature.

Email address is of form name@函.中国 (letter.china) I do not know what name validation they do but I assume name should be Chinese characters.