diff --git a/openbsc/include/openbsc/gsm_04_08.h b/openbsc/include/openbsc/gsm_04_08.h
index feb445b..485e240 100644
--- a/openbsc/include/openbsc/gsm_04_08.h
+++ b/openbsc/include/openbsc/gsm_04_08.h
@@ -724,7 +724,7 @@
 int gsm48_mi_to_string(char *string, const int str_len, const u_int8_t *mi, const int mi_len);
 
 int gsm48_send_rr_release(struct gsm_lchan *lchan);
-int gsm48_send_rr_ciph_mode(struct gsm_lchan *lchan);
+int gsm48_send_rr_ciph_mode(struct gsm_lchan *lchan, int want_imeisv);
 int gsm48_send_rr_app_info(struct gsm_lchan *lchan, u_int8_t apdu_id,
 			   u_int8_t apdu_len, u_int8_t *apdu);
 
diff --git a/openbsc/src/gsm_04_08.c b/openbsc/src/gsm_04_08.c
index 9ad9e15..9467d79 100644
--- a/openbsc/src/gsm_04_08.c
+++ b/openbsc/src/gsm_04_08.c
@@ -1644,30 +1644,6 @@
 	return rc;
 }
 
-/* Chapter 9.1.9: Ciphering Mode Command */
-int gsm48_send_rr_ciph_mode(struct gsm_lchan *lchan)
-{
-	struct msgb *msg = gsm48_msgb_alloc();
-	struct gsm48_hdr *gh;
-	u_int8_t ciph_mod_set;
-
-	msg->lchan = lchan;
-
-	DEBUGP(DRR, "TX CIPHERING MODE CMD\n");
-
-	if (lchan->encr.alg_id <= RSL_ENC_ALG_A5(0))
-		ciph_mod_set = 0;
-	else
-		ciph_mod_set = (lchan->encr.alg_id-2)<<1 | 1;
-
-	gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
-	gh->proto_discr = GSM48_PDISC_RR;
-	gh->msg_type = GSM48_MT_RR_CIPH_M_CMD;
-	gh->data[0] = 0x10 | (ciph_mod_set & 0xf);
-
-	return rsl_encryption_cmd(msg);
-}
-
 int gsm48_send_rr_app_info(struct gsm_lchan *lchan, u_int8_t apdu_id,
 			   u_int8_t apdu_len, u_int8_t *apdu)
 {
diff --git a/openbsc/src/gsm_04_08_utils.c b/openbsc/src/gsm_04_08_utils.c
index 47ec8ab..ef9e59c 100644
--- a/openbsc/src/gsm_04_08_utils.c
+++ b/openbsc/src/gsm_04_08_utils.c
@@ -457,3 +457,28 @@
 	paging_request_stop(msg->trx->bts, subscr, msg->lchan);
 	return 0;
 }
+
+/* Chapter 9.1.9: Ciphering Mode Command */
+int gsm48_send_rr_ciph_mode(struct gsm_lchan *lchan, int want_imeisv)
+{
+	struct msgb *msg = gsm48_msgb_alloc();
+	struct gsm48_hdr *gh;
+	u_int8_t ciph_mod_set;
+
+	msg->lchan = lchan;
+
+	DEBUGP(DRR, "TX CIPHERING MODE CMD\n");
+
+	if (lchan->encr.alg_id <= RSL_ENC_ALG_A5(0))
+		ciph_mod_set = 0;
+	else
+		ciph_mod_set = (lchan->encr.alg_id-2)<<1 | 1;
+
+	gh = (struct gsm48_hdr *) msgb_put(msg, sizeof(*gh) + 1);
+	gh->proto_discr = GSM48_PDISC_RR;
+	gh->msg_type = GSM48_MT_RR_CIPH_M_CMD;
+	gh->data[0] = (want_imeisv & 0x1) << 4 | (ciph_mod_set & 0xf);
+
+	return rsl_encryption_cmd(msg);
+}
+