Recently EAI WG of IETF has published standards for multilingual support in the local part of the e-mail address. Between 2009 and 2010, EAI WG published RFC documents, called the EAI standard, extension to the existing mail-related RFC documents, and EAI has been implemented and tested. In the course of reviewing the results, this yielded a proposal to modify the EAI standard. As a result, EAI WG has published modified RFC documents, called the EAI bis standard. SMTPUTF8 mail server described in this paper has been implemented according to the EAI bis standard. In addition, it has the ability to support two different standards to support the multilingual domain part of the e-mail address, IDNA and EAI bis. Futhermore, SMTPUTF8 mail server can encode in punycode the local part of the e-mail address. Finally, interoperability testing shows that SMTPUTF8 mail server is well-implemented according to the EAI bis standard.