+(defcustom diary-comment-start nil
+ "String marking the start of a comment in the diary, or nil.
+Nil means there are no comments. The diary does not display
+parts of entries that are inside comments. You can use comments
+for whatever you like, e.g. for meta-data that packages such as
+`appt.el' can use.
+See also `diary-comment-end'."
+ :version "24.1"
+ :type '(choice (const :tag "No comment" nil) string)
+ :group 'diary)
+
+(defcustom diary-comment-end ""
+ "String marking the end of a comment in the diary.
+The empty string means comments finish at the end of a line.
+See also `diary-comment-start'."
+ :version "24.1"
+ :type 'string
+ :group 'diary)
+