diff --git a/constants.h b/constants.h
index dcaf9fb8..486b5d48 100644
--- a/constants.h
+++ b/constants.h
@@ -77,6 +77,7 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 
 #define OVERLAY_MAX_LOCAL_IDENTITIES 256
 
+/* All of these types should be considered deprecated. Processing code should migrate to well known MDP port numbers */
 /* Overlay mesh packet codes */
 #define OF_TYPE_SELFANNOUNCE 0x10 /* BATMAN style announcement frames */
 #define OF_TYPE_SELFANNOUNCE_ACK 0x20 /* BATMAN style "I saw your announcment" frames */
@@ -98,6 +99,9 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
 #define PAYLOAD_FLAG_CIPHERED (1<<4)
 #define PAYLOAD_FLAG_SIGNED (1<<5)
 
+// this can be removed once all overlay messages have been turned into mdp payloads
+#define PAYLOAD_FLAG_LEGACY_TYPE (1<<7)
+
 /* Crypto/security options */
 #define OF_CRYPTO_NONE 0x00
 #define OF_CRYPTO_CIPHERED PAYLOAD_FLAG_CIPHERED /* Encrypted frame */
diff --git a/overlay_packetformats.c b/overlay_packetformats.c
index 7ea2cb2b..d37a0e81 100644
--- a/overlay_packetformats.c
+++ b/overlay_packetformats.c
@@ -265,9 +265,13 @@ int packetOkOverlay(struct overlay_interface *interface,unsigned char *packet, s
     f.ttl--;
     if (f.ttl<=0)
       forward=0;
-    f.type=ob_get(b);
-    if (f.type<0)
-      break;
+    
+    if (flags & PAYLOAD_FLAG_LEGACY_TYPE){
+      f.type=ob_get(b);
+      if (f.type<0)
+	break;
+    }else
+      f.type=OF_TYPE_DATA;
     
     f.modifiers=flags;
 
diff --git a/overlay_payload.c b/overlay_payload.c
index 274c833f..f6f05816 100644
--- a/overlay_payload.c
+++ b/overlay_payload.c
@@ -40,6 +40,9 @@ int overlay_frame_build_header(struct decode_context *context, struct overlay_bu
   if (!destination)
     flags |= PAYLOAD_FLAG_TO_BROADCAST;
   
+  if (type!=OF_TYPE_DATA)
+    flags |= PAYLOAD_FLAG_LEGACY_TYPE;
+  
   if (ob_append_byte(buff, flags)) return -1;
   
   if (!(flags & PAYLOAD_FLAG_SENDER_SAME)){
@@ -60,7 +63,10 @@ int overlay_frame_build_header(struct decode_context *context, struct overlay_bu
   if (!(flags & PAYLOAD_FLAG_ONE_HOP)){
     if (ob_append_byte(buff, ttl | ((queue&3)<<5))) return -1;
   }
-  if (ob_append_byte(buff, type)) return -1;
+  
+  if (flags & PAYLOAD_FLAG_LEGACY_TYPE){
+    if (ob_append_byte(buff, type)) return -1;
+  }
   
   if (ob_append_rfs(buff, 2)) return -1;