lisp/gnus/mml-sec.el (mml-secure-bcc-is-safe): Keep old Emacsen compatibility

* lisp/gnus/mml-sec.el (mml-secure-bcc-is-safe):
Don't use split-string with 4th arg for old Emacsen compatibility.

1 files changed, 2 insertions, 3 deletions

diff --git a/lisp/gnus/mml-sec.el b/lisp/gnus/mml-sec.el
index 4f57cb76ccc..fd01098fdcb 100644
--- a/lisp/gnus/mml-sec.el
+++ b/lisp/gnus/mml-sec.el
@@ -311,9 +311,8 @@ either an error is raised or not."
   (when (mml-secure-is-encrypted-p)
     (let ((bcc (mail-strip-quoted-names (message-fetch-field "bcc"))))
       (when bcc
-        ;; Split recipients at "," boundary, omit empty strings (t),
-        ;; and strip whitespace.
-        (let ((bcc-list (split-string bcc "," t "\\s-+")))
+        (let ((bcc-list (mapcar #'cadr
+                                (mail-extract-address-components bcc t))))
           (unless (gnus-subsetp bcc-list mml-secure-safe-bcc-list)
             (unless (yes-or-no-p "Message for encryption contains Bcc header.\
   This may give away all Bcc'ed identities to all recipients.\