diff --git a/openbsc/include/openbsc/mncc.h b/openbsc/include/openbsc/mncc.h
index 9153d6574..4a99bb11b 100644
--- a/openbsc/include/openbsc/mncc.h
+++ b/openbsc/include/openbsc/mncc.h
@@ -160,10 +160,20 @@ struct gsm_data_frame {
 	unsigned char	data[0];
 };
 
-#define MNCC_SOCK_VERSION	1
+#define MNCC_SOCK_VERSION	2
 struct gsm_mncc_hello {
 	uint32_t	msg_type;
 	uint32_t	version;
+
+	/* send the sizes of the structs */
+	uint32_t	mncc_size;
+	uint32_t	data_frame_size;
+
+	/* send some offsets */
+	uint32_t	called_offset;
+	uint32_t	signal_offset;
+	uint32_t	emergency_offset;
+	uint32_t	lchan_type_offset;
 };
 
 char *get_mncc_name(int value);
diff --git a/openbsc/src/libmsc/mncc_sock.c b/openbsc/src/libmsc/mncc_sock.c
index 697f9560f..cf4bca87a 100644
--- a/openbsc/src/libmsc/mncc_sock.c
+++ b/openbsc/src/libmsc/mncc_sock.c
@@ -2,6 +2,7 @@
 
 /* (C) 2008-2010 by Harald Welte <laforge@gnumonks.org>
  * (C) 2009 by Andreas Eversberg <Andreas.Eversberg@versatel.de>
+ * (C) 2012 by Holger Hans Peter Freyther
  * All Rights Reserved
  *
  * This program is free software; you can redistribute it and/or modify
@@ -221,6 +222,12 @@ static void queue_hello(struct mncc_sock_state *mncc)
 	hello = (struct gsm_mncc_hello *) msgb_put(msg, sizeof(*hello));
 	hello->msg_type = MNCC_SOCKET_HELLO;
 	hello->version = MNCC_SOCK_VERSION;
+	hello->mncc_size = sizeof(struct gsm_mncc);
+	hello->data_frame_size = sizeof(struct gsm_data_frame);
+	hello->called_offset = offsetof(struct gsm_mncc, called);
+	hello->signal_offset = offsetof(struct gsm_mncc, signal);
+	hello->emergency_offset = offsetof(struct gsm_mncc, emergency);
+	hello->lchan_type_offset = offsetof(struct gsm_mncc, lchan_type);
 
 	msgb_enqueue(&mncc->net->upqueue, msg);
 	mncc->conn_bfd.when |= BSC_FD_WRITE;