Change to citation regexp for mail-font-lock-keywords.

1 files changed, 14 insertions, 8 deletions

diff --git a/lisp/mail/sendmail.el b/lisp/mail/sendmail.el
index ea2a291aa15..a455e8d176d 100644
--- a/lisp/mail/sendmail.el
+++ b/lisp/mail/sendmail.el
@@ -199,14 +199,20 @@ actually occur.")
      (modify-syntax-entry ?% ". " mail-mode-syntax-table)))
 
 (defvar mail-font-lock-keywords
-  (list '("^To:" . font-lock-function-name-face)
-        '("^B?CC:\\|^Reply-To:" . font-lock-keyword-face)
-        '("^Subject:" . font-lock-comment-face)
-        '("^Subject:\\s *\\(.+\\)" 1 font-lock-type-face)
-        (list (concat "^\\(" (regexp-quote mail-header-separator) "\\)$") 1
-              'font-lock-comment-face)
-        '("^[ \t]*\\sw*[>|}].*" . font-lock-reference-face)     ; Citation.
-        '("^\\(X-[A-Za-z0-9-]+\\|In-reply-to\\):.*" . font-lock-string-face))
+  (eval-when-compile
+    (let* ((cite-prefix "A-Za-z") (cite-suffix (concat cite-prefix "0-9_.@-")))
+      (list '("^To:" . font-lock-function-name-face)
+            '("^B?CC:\\|^Reply-To:" . font-lock-keyword-face)
+            '("^\\(Subject:\\)[ \t]*\\(.+\\)?"
+              (1 font-lock-comment-face) (2 font-lock-type-face nil t))
+            (list (concat "^\\(" (regexp-quote mail-header-separator) "\\)$")
+                  1 'font-lock-comment-face)
+            (cons (concat "^[ \t]*"
+                          "\\([" cite-prefix "]+[" cite-suffix "]*\\)?"
+                          "[>|}].*")
+                  'font-lock-reference-face)
+            '("^\\(X-[A-Za-z0-9-]+\\|In-reply-to\\):.*"
+              . font-lock-string-face))))
   "Additional expressions to highlight in Mail mode.")
 
 (defvar mail-send-hook nil