+HOST_HIDING
+ * Type: boolean
+ * Default: FALSE
+
+This selects whether local users can set umode +x, thus allowing them
+to hide their hostname if they have also registered with a channel
+service (i.e. they have the ACCOUNT flag set).
+
+HIDDEN_HOST
+ * Type: string
+ * Default: users.undernet.org
+
+This selects the suffix for the hidden hostmask (see HOST_HIDING).
+