-(defun nnmail-fix-eudora-headers ()
- "Eudora has a broken References line, but an OK In-Reply-To."
+(defcustom nnmail-broken-references-mailers
+ "^X-Mailer:.*\\(Eudora\\|Pegasus\\)"
+ "Header line matching mailer producing bogus References lines.
+See `nnmail-ignore-broken-references'."
+ :group 'nnmail-prepare
+ :version "23.0" ;; No Gnus
+ :type 'regexp)
+
+(defun nnmail-ignore-broken-references ()
+ "Ignore the References line and use In-Reply-To
+
+Eudora has a broken References line, but an OK In-Reply-To."