I believe this issue had been discussed before but I'm sorry I could not find the exact bug id for this. Please close as dup if the same bug already exists. If people sends e-mail with EUC or SJIS plain text in mail attachment, and receiver tries to store the attachmen to the file, currently the file is stored as ISO-2022-JP. But usually receiver wants the file as the original character encoding. After the file is stored as ISO-2022-JP, if receiver is end user, I believe he/she can not find the way how to display japanese properly. I can not ask such enduser to use iconv. Is there any good preference to set character encoding for storing attachment? For example, ISO-2022-JP is japanese, running locale is EUC, then store the attachment is EUC. We need to have preference of character encoding like composer. But it would not be good enough. We need to provide the default value such as Japanese-EUC for suggestion.