1 files changed, 1 insertions, 0 deletions

diff --git a/lisp/gnus/smime.el b/lisp/gnus/smime.el
index 0695d5ac82e..27db3e35e20 100644
--- a/lisp/gnus/smime.el
+++ b/lisp/gnus/smime.el
@@ -428,6 +428,7 @@ Any details (stdout and stderr) are left in the buffer specified by
 
 (defun smime-decrypt-region (b e keyfile &optional from)
   "Decrypt S/MIME message in region between B and E with key in KEYFILE.
+Optional FROM specifies sender's mail address.
 On success, replaces region with decrypted data and return non-nil.
 Any details (stderr on success, stdout and stderr on error) are left
 in the buffer specified by `smime-details-buffer'."