+(defcustom spam-stat-washing-hook nil
+ "Hook applied to each message before analysis."
+ :type 'hook
+ :group 'spam-stat)
+
+(defcustom spam-stat-process-directory-age 90
+ "Max. age of files to be processed in directory, in days.
+When using `spam-stat-process-spam-directory' or
+`spam-stat-process-non-spam-directory', only files that have
+been touched in this many days will be considered. Without
+this filter, re-training spam-stat with several thousand messages
+will start to take a very long time.")
+