ASP.NET i18n setting.
<globalization requestencoding="utf-8" responseencoding="utf-8" fileencoding="utf-8"></globalization>If UTF-8 does not solve the problem for some reasons or feeling it is too consuming bytes since it standardize to 2 bytes.
use each language codec (multibyte mode) by specify.
<globalization requestencoding="euc-jp" responseencoding="euc-jp" enablebestfitresponseencoding="true"></globalization>
Note: the language codec must be installed of course in the first place.