diff --git a/include/osmocom/bsc/abis_rsl.h b/include/osmocom/bsc/abis_rsl.h
index 098d2e6ee..ec630909c 100644
--- a/include/osmocom/bsc/abis_rsl.h
+++ b/include/osmocom/bsc/abis_rsl.h
@@ -90,7 +90,7 @@ int rsl_chan_ms_power_ctrl(struct gsm_lchan *lchan, unsigned int fpc, int dbm);
 /* SMSCB functionality */
 int rsl_sms_cb_command(struct gsm_bts *bts, uint8_t chan_number,
 		       struct rsl_ie_cb_cmd_type cb_command,
-		       const uint8_t *data, int len);
+		       bool use_extended_cbch, const uint8_t *data, int len);
 
 /* some Nokia specific stuff */
 int rsl_nokia_si_begin(struct gsm_bts_trx *trx);
diff --git a/src/osmo-bsc/abis_rsl.c b/src/osmo-bsc/abis_rsl.c
index bc0745775..5a1c8ff7f 100644
--- a/src/osmo-bsc/abis_rsl.c
+++ b/src/osmo-bsc/abis_rsl.c
@@ -2172,7 +2172,7 @@ int abis_rsl_rcvmsg(struct msgb *msg)
 
 int rsl_sms_cb_command(struct gsm_bts *bts, uint8_t chan_number,
 		       struct rsl_ie_cb_cmd_type cb_command,
-		       const uint8_t *data, int len)
+		       bool use_extended_cbch, const uint8_t *data, int len)
 {
 	struct abis_rsl_dchan_hdr *dh;
 	struct msgb *cb_cmd;
@@ -2188,6 +2188,8 @@ int rsl_sms_cb_command(struct gsm_bts *bts, uint8_t chan_number,
 
 	msgb_tv_put(cb_cmd, RSL_IE_CB_CMD_TYPE, *(uint8_t*)&cb_command);
 	msgb_tlv_put(cb_cmd, RSL_IE_SMSCB_MSG, len, data);
+	if (use_extended_cbch)
+		msgb_tv_put(cb_cmd, RSL_IE_SMSCB_CHAN_INDICATOR, 0x01);
 
 	cb_cmd->dst = bts->c0->rsl_link;
 
diff --git a/src/osmo-bsc/bsc_vty.c b/src/osmo-bsc/bsc_vty.c
index dc97d1242..88c845b6d 100644
--- a/src/osmo-bsc/bsc_vty.c
+++ b/src/osmo-bsc/bsc_vty.c
@@ -4582,7 +4582,7 @@ DEFUN(smscb_cmd, smscb_cmd_cmd,
 		return CMD_WARNING;
 	}
 
-	rsl_sms_cb_command(bts, RSL_CHAN_SDCCH4_ACCH, cb_cmd, buf, rc);
+	rsl_sms_cb_command(bts, RSL_CHAN_SDCCH4_ACCH, cb_cmd, false, buf, rc);
 
 	return CMD_SUCCESS;
 }