+extern int gras_msg_libdata_id; /* The identifier of our libdata */
+
+extern const char *e_gras_msg_kind_names[e_gras_msg_kind_count];
+
+/* declare either regular messages or RPC or whatever */
+void
+gras_msgtype_declare_ext(const char *name,
+ short int version,
+ e_gras_msg_kind_t kind,
+ gras_datadesc_type_t payload_request,
+ gras_datadesc_type_t payload_answer);