+(defun message-xmas-make-date (&optional now)
+ "Make a valid data header.
+If NOW, use that time instead."
+ (let ((zone (car (current-time-zone)))
+ sign)
+ (if (>= zone 0)
+ (setq sign "+")
+ (setq sign "-"
+ zone (- zone)))
+ (format "%s %s%02d%02d"
+ (format-time-string "%a, %d %b %Y %T" now)
+ sign
+ (/ zone 3600)
+ (/ (% zone 3600) 60))))
+