Set this variable to 1 to display the fully qualified domain name (FQDN) of
hosts in Spong client displays. Otherwise only the first element of the FQDN
-will be displayed.
+will be displayed. If the host has a 'display_name' attribute, it will be used
+in preference to the FQDN names.
+
+=item $HISTORY_FQDN
+
+Set this varirable to 1 to display teh fully qualified domain name (FQDN) of
+hosts in History displays display clients. Otherwise only the first element of
+the FQDN will be displayed. If the host has a 'display_name' attribute, it will
+be used in preference to the FQDN names.
+
=item $SEND_MESSAGE