gnus-sum.el (gnus-extra-headers): Add Keywords, Cc, and Gcc to default.

gnus-registry.el: Mention in comments how to modify `gnus-extra-headers' for proper recipient tracking and that it may already have To and Cc recently, which it does as of this commit.

lisp/gnus/ChangeLog

 2011-04-21  Teodor Zlatanov  <tzz@lifelogs.com>
+	* gnus-sum.el (gnus-extra-headers): Add Keywords, Cc, and Gcc to
+	default.
+
 	* gnus.el (gnus-registry-ignored-groups): Provide default in gnus.el,
 	not gnus-registry.el.
-	* gnus-registry.el (gnus-registry-ignored-groups): Remove defcustom.
+	* gnus-registry.el: Mention in comments how to modify
+	`gnus-extra-headers' for proper recipient tracking and that it may
+	already have To and Cc recently, which it does as of this commit.
+	(gnus-registry-ignored-groups): Remove defcustom.
 	Explain why in comments.
 	(gnus-registry-action): Fix data-header reference to use the extra
 	headers.  Explain in package commentary how to add To and Cc headers to

lisp/gnus/gnus-registry.el

@@ -35,7 +35,8 @@
 
 ;; If you want to track recipients (and you should to make the
 ;; gnus-registry splitting work better), you need the To and Cc
-;; headers collected by Gnus:
+;; headers collected by Gnus.  Note that in more recent Gnus versions
+;; this is already the case: look at `gnus-extra-headers' to be sure.
 
 ;; ;;; you may also want Gcc Newsgroups Keywords X-Face
 ;; (add-to-list 'gnus-extra-headers 'To)

lisp/gnus/gnus-sum.el

@@ -1128,7 +1128,7 @@ which it may alter in any way."
   'mail-decode-encoded-address-string
   "Function used to decode addresses with encoded words.")
 
-(defcustom gnus-extra-headers '(To Newsgroups)
+(defcustom gnus-extra-headers '(To Cc Keywords Gcc Newsgroups)
   "*Extra headers to parse."
   :version "21.1"
   :group 'gnus-summary