diff --git a/openbsc/include/openbsc/bsc_api.h b/openbsc/include/openbsc/bsc_api.h
index 472c8e4..f52984f 100644
--- a/openbsc/include/openbsc/bsc_api.h
+++ b/openbsc/include/openbsc/bsc_api.h
@@ -34,6 +34,13 @@
 	void (*classmark_chg)(struct gsm_subscriber_connection *conn,
 			      const uint8_t *cm2, uint8_t cm2_len,
 			      const uint8_t *cm3, uint8_t cm3_len);
+
+	/**
+	 * Configure the multirate setting on this channel. If it is
+	 * not implemented AMR5.9 will be used.
+	 */
+	void (*mr_config)(struct gsm_subscriber_connection *conn,
+			  struct gsm48_multi_rate_conf *conf);
 };
 
 int bsc_api_init(struct gsm_network *network, struct bsc_api *api);
diff --git a/openbsc/include/openbsc/osmo_msc_data.h b/openbsc/include/openbsc/osmo_msc_data.h
index 6eebcdd..8e255a0 100644
--- a/openbsc/include/openbsc/osmo_msc_data.h
+++ b/openbsc/include/openbsc/osmo_msc_data.h
@@ -26,6 +26,7 @@
 #include "bsc_msc.h"
 
 #include <osmocom/core/timer.h>
+#include <osmocom/gsm/protocol/gsm_04_08.h>
 
 #include <regex.h>
 
@@ -68,6 +69,7 @@
 	int rtp_base;
 
 	/* audio codecs */
+	struct gsm48_multi_rate_conf amr_conf;
 	struct gsm_audio_support **audio_support;
 	int audio_length;