diff --git a/Makefile b/Makefile
index 12eb37ef772..d7b6df41588 100644
--- a/Makefile
+++ b/Makefile
@@ -124,7 +124,6 @@ misc:
 multimon:
 	cd $(MULTIMON); $(MAKE)
 
-#static_h: $(MESSAGES_H) $(MESSAGES2_H) $(UBX_PROTOCOL_H) $(MTK_PROTOCOL_H) $(XSENS_PROTOCOL_H) $(DL_PROTOCOL_H) $(DL_PROTOCOL2_H)
 static_h: $(MESSAGES_XML) $(UBX_PROTOCOL_H) $(MTK_PROTOCOL_H) $(XSENS_PROTOCOL_H)
 
 usb_lib:
@@ -134,20 +133,6 @@ $(MESSAGES_XML) : $(MESSAGES_XML_CONF) tools
 	@echo BUILD $@
 	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages_xml.out $(MESSAGES_XML_CONF) $(MESSAGES_FILES) $@ $(STATICINCLUDE)
 
-#$(MESSAGES_H) : $(MESSAGES_XML) $(CONF_XML) tools
-#	$(Q)test -d $(STATICINCLUDE) || mkdir -p $(STATICINCLUDE)
-#	@echo BUILD $@
-#	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages.out $< telemetry > /tmp/msg.h
-#	$(Q)mv /tmp/msg.h $@
-#	$(Q)chmod a+r $@
-
-#$(MESSAGES2_H) : $(MESSAGES_XML) $(CONF_XML) tools
-#	$(Q)test -d $(STATICINCLUDE) || mkdir -p $(STATICINCLUDE)
-#	@echo BUILD $@
-#	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages2.out $< telemetry > /tmp/msg2.h
-#	$(Q)mv /tmp/msg2.h $@
-#	$(Q)chmod a+r $@
-
 $(UBX_PROTOCOL_H) : $(UBX_XML) tools
 	@echo BUILD $@
 	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_ubx.out $< > /tmp/ubx.h
@@ -163,15 +148,6 @@ $(XSENS_PROTOCOL_H) : $(XSENS_XML) tools
 	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_xsens.out $< > /tmp/xsens.h
 	$(Q)mv /tmp/xsens.h $@
 
-#$(DL_PROTOCOL_H) : $(MESSAGES_XML) tools
-#	@echo BUILD $@
-#	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages.out $< datalink > /tmp/dl.h
-#	$(Q)mv /tmp/dl.h $@
-
-#$(DL_PROTOCOL2_H) : $(MESSAGES_XML) tools
-#	@echo BUILD $@
-#	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages2.out $< datalink > /tmp/dl2.h
-#	$(Q)mv /tmp/dl2.h $@
 
 include Makefile.ac
 
@@ -241,12 +217,10 @@ fast_deb:
 
 clean:
 	$(Q)rm -fr dox build-stamp configure-stamp conf/%gconf.xml debian/files debian/paparazzi-base debian/paparazzi-bin
-#	$(Q)rm -f  $(MESSAGES_H) $(MESSAGES2_H) $(UBX_PROTOCOL_H) $(MTK_PROTOCOL_H) $(DL_PROTOCOL_H)
 	$(Q)find . -mindepth 2 -name Makefile -exec sh -c 'echo "Cleaning {}"; $(MAKE) -C `dirname {}` $@' \;
 	$(Q)find . -name '*~' -exec rm -f {} \;
 	$(Q)rm -f paparazzi sw/simulator/launchsitl
 	$(Q)rm -f $(STATICINCLUDE)/*
-	$(Q)rm -f $(MESSAGES_XML_CONF)
 
 cleanspaces:
 	find ./sw/airborne -name '*.[ch]' -exec sed -i {} -e 's/[ \t]*$$//' \;
@@ -263,6 +237,7 @@ dist_clean_irreversible: clean
 	rm -rf conf/maps_data conf/maps.xml
 	rm -rf conf/conf.xml conf/controlpanel.xml
 	rm -rf var
+	rm -f $(MESSAGES_XML_CONF)
 
 ab_clean:
 	find sw/airborne -name '*~' -exec rm -f {} \;
@@ -284,16 +259,11 @@ sw/simulator/launchsitl:
 	cat src/$(@F) | sed s#OCAMLRUN#$(OCAMLRUN)# | sed s#OCAML#$(OCAML)# > $@
 	chmod a+x $@
 
-
-
-
-
 gen_messages_macros: $(MACROS_TARGET)
 
-#$(MACROS_TARGET) : $(MESSAGES_XML) $(CONF_XML) tools
-$(MACROS_TARGET) : 
+$(MACROS_TARGET) : $(MESSAGES_XML_CONF) tools
 	@echo BUILD $@
-	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages.out $(MESSAGES_XML) $(MACROS_CLASS) $(MACROS_ALIGN) > /tmp/msg.h
+	$(Q)PAPARAZZI_SRC=$(PAPARAZZI_SRC) PAPARAZZI_HOME=$(PAPARAZZI_HOME) $(TOOLS)/gen_messages.out $(MESSAGES_XML) $(MACROS_CLASS) $(MACROS_CLASS_ID) $(MACROS_ALIGN) > /tmp/msg.h
 	$(Q)mv /tmp/msg.h $@
 	$(Q)chmod a+r $@
 
diff --git a/sw/airborne/firmwares/fixedwing/datalink.c b/sw/airborne/firmwares/fixedwing/datalink.c
index 553bb828df2..c8dd6d777d7 100644
--- a/sw/airborne/firmwares/fixedwing/datalink.c
+++ b/sw/airborne/firmwares/fixedwing/datalink.c
@@ -66,8 +66,9 @@
 
 #define MOfCm(_x) (((float)(_x))/100.)
 
-#define SenderIdOfMsg(x) (x[0])
-#define IdOfMsg(x) (x[1])
+#define SenderIdOfMsg(x) (x[1])
+#define IdOfClass(x) (x[2])
+#define IdOfMsg(x) (x[3])
 
 void dl_parse_msg(void) {
   datalink_time = 0;
diff --git a/sw/airborne/firmwares/rotorcraft/datalink.c b/sw/airborne/firmwares/rotorcraft/datalink.c
index 931663c4274..e910b45317e 100644
--- a/sw/airborne/firmwares/rotorcraft/datalink.c
+++ b/sw/airborne/firmwares/rotorcraft/datalink.c
@@ -43,7 +43,7 @@
 #include "math/pprz_geodetic_int.h"
 #include "subsystems/ins.h"
 
-#define IdOfMsg(x) (x[1])
+#define IdOfMsg(x) (x[3])
 
 void dl_parse_msg(void) {
 
diff --git a/sw/airborne/subsystems/datalink/pprz_transport.c b/sw/airborne/subsystems/datalink/pprz_transport.c
index 6c234a47dec..ca2f2f9c9fa 100644
--- a/sw/airborne/subsystems/datalink/pprz_transport.c
+++ b/sw/airborne/subsystems/datalink/pprz_transport.c
@@ -26,6 +26,6 @@
 #include "subsystems/datalink/pprz_transport.h"
 #include "mcu_periph/uart.h"
 
-uint8_t ck_a, ck_b;
+uint8_t ck_a, ck_b, down_packet_seq;
 
 struct pprz_transport pprz_tp;
diff --git a/sw/airborne/subsystems/datalink/transport.h b/sw/airborne/subsystems/datalink/transport.h
index 09d42ab980f..441443354ea 100644
--- a/sw/airborne/subsystems/datalink/transport.h
+++ b/sw/airborne/subsystems/datalink/transport.h
@@ -45,6 +45,8 @@ struct transport {
   volatile bool_t msg_received;
   // overrun and error flags
   uint8_t ovrn, error;
+  // packet sequence
+  uint8_t packet_seq;
 };
 
 /** Transport link macros
diff --git a/sw/airborne/subsystems/datalink/xbee.c b/sw/airborne/subsystems/datalink/xbee.c
index 9d1c2aedf56..a1e13259959 100644
--- a/sw/airborne/subsystems/datalink/xbee.c
+++ b/sw/airborne/subsystems/datalink/xbee.c
@@ -32,6 +32,7 @@
 
 uint8_t xbee_cs;
 uint8_t xbee_rssi;
+uint8_t down_packet_seq;
 
 struct xbee_transport xbee_tp;
 
diff --git a/sw/lib/ocaml/convert.c b/sw/lib/ocaml/convert.c
index 450d764aa46..6496d580aa0 100644
--- a/sw/lib/ocaml/convert.c
+++ b/sw/lib/ocaml/convert.c
@@ -82,6 +82,13 @@ c_sprint_int32(value s, value index, value x) {
   return Val_unit;
 }
 
+value
+c_sprint_int64(value s, value index, value x) {
+  int64_t *p = (int64_t*) (String_val(s) + Int_val(index));
+  *p = (int64_t)Int64_val(x);
+  return Val_unit;
+}
+
 value
 c_int16_of_indexed_bytes(value s, value index)
 {
@@ -105,3 +112,11 @@ c_int32_of_indexed_bytes(value s, value index)
 
   return copy_int32(*x);
 }
+
+value
+c_int64_of_indexed_bytes(value s, value index)
+{
+  int64_t *x = (int64_t*)(String_val(s) + Int_val(index));
+
+  return copy_int64(*x);
+}
diff --git a/sw/tools/gen_messages_xml.ml b/sw/tools/gen_messages_xml.ml
index 18b1d57255b..807bbecf3ce 100644
--- a/sw/tools/gen_messages_xml.ml
+++ b/sw/tools/gen_messages_xml.ml
@@ -231,19 +231,19 @@ module MakeCalls = struct
 	let make_target = "gen_messages_macros"
 	let make_options = ""
 	
-	let make = fun class_name check_alignment ->
+	let make = fun class_name class_id check_alignment ->
 		let file = Env.paparazzi_home // "Makefile" in
 		let macros_target = var_include_path // ("messages_"^(String.lowercase class_name)^".h") in
-		let c = sprintf "make -f %s MACROS_TARGET=%s MACROS_CLASS=%s MACROS_ALIGN=%u %s %s" file macros_target class_name check_alignment make_options make_target in
+		let c = sprintf "make -f %s MACROS_TARGET=%s MACROS_CLASS=%s MACROS_CLASS_ID=%s MACROS_ALIGN=%u %s %s" file macros_target class_name class_id check_alignment make_options make_target in
     let returned_code = Sys.command c in
     if returned_code <> 0 then failwith (sprintf "Make command error (Error code: %d)" returned_code) 
 
 
 	let generate_macros = fun classes ->
 		List.map (fun clas -> match (clas.g_type) with 
-			| "datalink" -> prerr_endline ("\t Datalink Class -> Generate macros ("^clas.g_name^") [Check Alignment]"); make clas.g_name 1
-			| "uplink" -> prerr_endline ("\t Uplink Class   -> Generate macros ("^clas.g_name^") [Check Alignment]"); make clas.g_name 1 
-			| "downlink" -> prerr_endline ("\t Downlink Class -> Generate macros ("^clas.g_name^")"); make clas.g_name 0
+			| "datalink" -> prerr_endline ("\t Datalink Class -> Generate macros ("^clas.g_name^") [Check Alignment]"); make clas.g_name clas.g_id 1
+			| "uplink" -> prerr_endline ("\t Uplink Class   -> Generate macros ("^clas.g_name^") [Check Alignment]"); make clas.g_name clas.g_id 1 
+			| "downlink" -> prerr_endline ("\t Downlink Class -> Generate macros ("^clas.g_name^")"); make clas.g_name clas.g_id 0
 			|	"ground" -> prerr_endline ("\t Ground Class   -> Do nothing ("^clas.g_name^")")
 			|	"airborne" -> prerr_endline ("\t Airborne Class -> Generate macros ("^clas.g_name^") ¡¡¡FIXME!!!")
 			|	t -> failwith (sprintf "Invalid class type in generated file: %s" t)