"Default coding system for encoding the outgoing mail.
This variable is used only when `sendmail-coding-system' is nil.
-This variable is set/changed by the command set-language-environment.
+This variable is set/changed by the command `set-language-environment'.
User should not set this variable manually,
-instead use sendmail-coding-system to get a constant encoding
+instead use `sendmail-coding-system' to get a constant encoding
of outgoing mails regardless of the current language environment.
See also the function `select-message-coding-system'.")