Coding when sending a message

Dmitry Dereyankin. Thank you very much for the example, easily realized it at home. But there is a problem. If msg = mimetext ('') contains only Latin, then everything is fine. But if it is Cyrillic, then there are problems with the encoding: a = "Plain" "Part = mimetext (a)

result: & Eth; & Plusmn; & Eth; & Raquo; & Ntilde; & Ntilde; & Hellip; & Eth; & Deg;

At the same time, the theme of the letter is normally displayed both by Latin and Cyrillic. Thank you in advance for the answer to the stupid noob question.