diff --git a/src/libmsc/gsm_04_11.c b/src/libmsc/gsm_04_11.c
index 45b56d2..f82aa6d 100644
--- a/src/libmsc/gsm_04_11.c
+++ b/src/libmsc/gsm_04_11.c
@@ -993,7 +993,7 @@
 	struct msgb *msg = gsm411_msgb_alloc();
 	struct gsm_trans *trans;
 	uint8_t *data, *rp_ud_len;
-	uint8_t msg_ref = sms_next_rp_msg_ref(&conn->next_rp_ref);
+	uint8_t msg_ref = conn->next_rp_ref++;
 	int transaction_id;
 	int rc;