diff --git a/openbsc/doc/channel_release.txt b/openbsc/doc/channel_release.txt
index bd707b4..c9cdfeb 100644
--- a/openbsc/doc/channel_release.txt
+++ b/openbsc/doc/channel_release.txt
@@ -61,7 +61,8 @@
 	* Release all SAPI's > 0 as local end (The BTS should send a
 	  REL_CONF a message)
 	* Send SACH Deactivate on SAPI=0 if required.
-	* It should start T3109 but it does not.
+	* Start T3109 (stop it when the main signalling link is disconnected)
+	  or when the channel released. On timeout start the error handling.
 	* abis_rsl.c schedules the RSL_MT_RF_CHAN_REL once all SAPI's are
 	  released and after T3111 has timed out or there is an error.
 
diff --git a/openbsc/doc/examples/osmo-nitb/bs11/openbsc-1bts-2trx-hopping.cfg b/openbsc/doc/examples/osmo-nitb/bs11/openbsc-1bts-2trx-hopping.cfg
index 654d397..36065e2 100644
--- a/openbsc/doc/examples/osmo-nitb/bs11/openbsc-1bts-2trx-hopping.cfg
+++ b/openbsc/doc/examples/osmo-nitb/bs11/openbsc-1bts-2trx-hopping.cfg
@@ -30,7 +30,7 @@
  timer t3103 0
  timer t3105 0
  timer t3107 0
- timer t3109 0
+ timer t3109 4
  timer t3111 0
  timer t3113 60
  timer t3115 0
diff --git a/openbsc/doc/examples/osmo-nitb/hsl/openbsc.cfg b/openbsc/doc/examples/osmo-nitb/hsl/openbsc.cfg
index 3d95748..b0af855 100644
--- a/openbsc/doc/examples/osmo-nitb/hsl/openbsc.cfg
+++ b/openbsc/doc/examples/osmo-nitb/hsl/openbsc.cfg
@@ -31,7 +31,7 @@
  timer t3103 0
  timer t3105 0
  timer t3107 0
- timer t3109 0
+ timer t3109 4
  timer t3111 0
  timer t3113 60
  timer t3115 0
diff --git a/openbsc/doc/examples/osmo-nitb/nanobts/openbsc-multitrx.cfg b/openbsc/doc/examples/osmo-nitb/nanobts/openbsc-multitrx.cfg
index 7a187f8..bea0b7d 100644
--- a/openbsc/doc/examples/osmo-nitb/nanobts/openbsc-multitrx.cfg
+++ b/openbsc/doc/examples/osmo-nitb/nanobts/openbsc-multitrx.cfg
@@ -30,7 +30,7 @@
  timer t3103 0
  timer t3105 0
  timer t3107 0
- timer t3109 0
+ timer t3109 4
  timer t3111 0
  timer t3113 60
  timer t3115 0
diff --git a/openbsc/doc/examples/osmo-nitb/nanobts/openbsc.cfg b/openbsc/doc/examples/osmo-nitb/nanobts/openbsc.cfg
index 78e9787..7a44308 100644
--- a/openbsc/doc/examples/osmo-nitb/nanobts/openbsc.cfg
+++ b/openbsc/doc/examples/osmo-nitb/nanobts/openbsc.cfg
@@ -30,7 +30,7 @@
  timer t3103 0
  timer t3105 0
  timer t3107 0
- timer t3109 0
+ timer t3109 4
  timer t3111 0
  timer t3113 60
  timer t3115 0
diff --git a/openbsc/doc/examples/osmo-nitb/rbs2308/openbsc.cfg b/openbsc/doc/examples/osmo-nitb/rbs2308/openbsc.cfg
index 7135042..97cd9df 100644
--- a/openbsc/doc/examples/osmo-nitb/rbs2308/openbsc.cfg
+++ b/openbsc/doc/examples/osmo-nitb/rbs2308/openbsc.cfg
@@ -29,7 +29,7 @@
  timer t3103 0
  timer t3105 0
  timer t3107 0
- timer t3109 0
+ timer t3109 4
  timer t3111 0
  timer t3113 60
  timer t3115 0
diff --git a/openbsc/include/openbsc/abis_rsl.h b/openbsc/include/openbsc/abis_rsl.h
index 45af4a6..4f2b6b5 100644
--- a/openbsc/include/openbsc/abis_rsl.h
+++ b/openbsc/include/openbsc/abis_rsl.h
@@ -99,6 +99,7 @@
 
 int rsl_release_sapis_from(struct gsm_lchan *lchan, int start,
 				enum rsl_rel_mode release_mode);
+int rsl_start_t3109(struct gsm_lchan *lchan);
 
 #endif /* RSL_MT_H */
 
diff --git a/openbsc/include/openbsc/gsm_data_shared.h b/openbsc/include/openbsc/gsm_data_shared.h
index 21fa645..ba431da 100644
--- a/openbsc/include/openbsc/gsm_data_shared.h
+++ b/openbsc/include/openbsc/gsm_data_shared.h
@@ -217,6 +217,7 @@
 
 #ifdef ROLE_BSC
 	struct osmo_timer_list T3101;
+	struct osmo_timer_list T3109;
 	struct osmo_timer_list T3111;
 	struct osmo_timer_list error_timer;
 	struct osmo_timer_list act_timer;
diff --git a/openbsc/src/libbsc/abis_rsl.c b/openbsc/src/libbsc/abis_rsl.c
index 04d5c61..6e1ce78 100644
--- a/openbsc/src/libbsc/abis_rsl.c
+++ b/openbsc/src/libbsc/abis_rsl.c
@@ -46,6 +46,11 @@
 #define RSL_ALLOC_SIZE		1024
 #define RSL_ALLOC_HEADROOM	128
 
+enum sacch_deact {
+	SACCH_NONE,
+	SACCH_DEACTIVATE,
+};
+
 static int rsl_send_imm_assignment(struct gsm_lchan *lchan);
 
 static void send_lchan_signal(int sig_no, struct gsm_lchan *lchan,
@@ -644,12 +649,16 @@
 static int rsl_rx_rf_chan_rel_ack(struct gsm_lchan *lchan);
 
 /* Chapter 8.4.14 / 4.7: Tell BTS to release the radio channel */
-static int rsl_rf_chan_release(struct gsm_lchan *lchan, int error)
+static int rsl_rf_chan_release(struct gsm_lchan *lchan, int error,
+				enum sacch_deact deact_sacch)
 {
 	struct abis_rsl_dchan_hdr *dh;
 	struct msgb *msg;
 	int rc;
 
+	/* Stop timers that should lead to a channel release */
+	osmo_timer_del(&lchan->T3109);
+
 	if (lchan->state == LCHAN_S_REL_ERR) {
 		LOGP(DRSL, LOGL_NOTICE, "%s is in error state not sending release.\n",
 		     gsm_lchan_name(lchan));
@@ -688,7 +697,8 @@
 		/*
 		 * sacch de-activate and "local end release"
 		 */
-		rsl_deact_sacch(lchan);
+		if (deact_sacch == SACCH_DEACTIVATE)
+			rsl_deact_sacch(lchan);
 		rsl_release_sapis_from(lchan, 0, RSL_REL_LOCAL_END);
 
 		/*
@@ -939,7 +949,7 @@
 		if (*cause != RSL_ERR_RCH_ALR_ACTV_ALLOC)
 			rsl_lchan_set_state(msg->lchan, LCHAN_S_BROKEN);
 		else
-			rsl_rf_chan_release(msg->lchan, 1);
+			rsl_rf_chan_release(msg->lchan, 1, SACCH_DEACTIVATE);
 
 	} else
 		rsl_lchan_set_state(msg->lchan, LCHAN_S_BROKEN);
@@ -969,7 +979,7 @@
 	LOGPC(DRSL, LOGL_NOTICE, "\n");
 	/* FIXME: only free it after channel release ACK */
 	osmo_counter_inc(msg->lchan->ts->trx->bts->network->stats.chan.rf_fail);
-	return rsl_rf_chan_release(msg->lchan, 1);
+	return rsl_rf_chan_release(msg->lchan, 1, SACCH_DEACTIVATE);
 }
 
 static void print_meas_rep_uni(struct gsm_meas_rep_unidir *mru,
@@ -1250,7 +1260,7 @@
 {
 	struct gsm_lchan *lchan = data;
 
-	rsl_rf_chan_release(lchan, 1);
+	rsl_rf_chan_release(lchan, 1, SACCH_DEACTIVATE);
 }
 
 /* If T3111 expires, we will send the RF Channel Request */
@@ -1258,7 +1268,17 @@
 {
 	struct gsm_lchan *lchan = data;
 
-	rsl_rf_chan_release(lchan, 0);
+	rsl_rf_chan_release(lchan, 0, SACCH_NONE);
+}
+
+/* If T3109 expires the MS has not send a UA/UM do the error release */
+static void t3109_expired(void *data)
+{
+	struct gsm_lchan *lchan = data;
+
+	LOGP(DRSL, LOGL_ERROR,
+		"%s SACCH deactivation timeout.\n", gsm_lchan_name(lchan));
+	rsl_rf_chan_release(lchan, 1, SACCH_NONE);
 }
 
 #define GSM48_LEN2PLEN(a)	(((a) << 2) | 1)
@@ -1516,7 +1536,7 @@
 
 	if (rlm_cause[1] == RLL_CAUSE_T200_EXPIRED) {
 		osmo_counter_inc(msg->lchan->ts->trx->bts->network->stats.chan.rll_err);
-		return rsl_rf_chan_release(msg->lchan, 1);
+		return rsl_rf_chan_release(msg->lchan, 1, SACCH_DEACTIVATE);
 	}
 
 	return 0;
@@ -1544,8 +1564,8 @@
 	}
 
 
-
-	/* wait a bit to send the RF Channel Release */
+	/* Stop T3109 and wait for T3111 before re-using the channel */
+	osmo_timer_del(&lchan->T3109);
 	lchan->T3111.cb = t3111_expired;
 	lchan->T3111.data = lchan;
 	bts = lchan->ts->trx->bts;
@@ -2107,3 +2127,17 @@
 
 	return no_sapi;
 }
+
+int rsl_start_t3109(struct gsm_lchan *lchan)
+{
+	struct gsm_bts *bts = lchan->ts->trx->bts;
+
+	/* Disabled, mostly legacy code */
+	if (bts->network->T3109 == 0)
+		return -1;
+
+	lchan->T3109.cb = t3109_expired;
+	lchan->T3109.data = lchan;
+	osmo_timer_schedule(&lchan->T3109, bts->network->T3109, 0);
+	return 0;
+}
diff --git a/openbsc/src/libbsc/bsc_vty.c b/openbsc/src/libbsc/bsc_vty.c
index 61b0911..dfe80c9 100644
--- a/openbsc/src/libbsc/bsc_vty.c
+++ b/openbsc/src/libbsc/bsc_vty.c
@@ -1379,7 +1379,7 @@
 DECLARE_TIMER(3103, "Set the timeout value for HANDOVER.\n")
 DECLARE_TIMER(3105, "Set the timer for repetition of PHYSICAL INFORMATION.\n")
 DECLARE_TIMER(3107, "Currently not used.\n")
-DECLARE_TIMER(3109, "Currently not used.\n")
+DECLARE_TIMER(3109, "Set the RSL SACCH deactivation timeout.\n")
 DECLARE_TIMER(3111, "Set the RSL timeout to wait before releasing the RF Channel.\n")
 DECLARE_TIMER(3113, "Set the time to try paging a subscriber.\n")
 DECLARE_TIMER(3115, "Currently not used.\n")
diff --git a/openbsc/src/libbsc/chan_alloc.c b/openbsc/src/libbsc/chan_alloc.c
index a8b15d1..9b59d5d 100644
--- a/openbsc/src/libbsc/chan_alloc.c
+++ b/openbsc/src/libbsc/chan_alloc.c
@@ -362,6 +362,7 @@
 void lchan_reset(struct gsm_lchan *lchan)
 {
 	osmo_timer_del(&lchan->T3101);
+	osmo_timer_del(&lchan->T3109);
 	osmo_timer_del(&lchan->T3111);
 	osmo_timer_del(&lchan->error_timer);
 
@@ -376,7 +377,7 @@
 
 /* Drive the release process of the lchan */
 static void _lchan_handle_release(struct gsm_lchan *lchan,
-				  int sach_deact, int mode)
+				  int sacch_deact, int mode)
 {
 	/* Release all SAPIs on the local end and continue */
 	rsl_release_sapis_from(lchan, 1, RSL_REL_LOCAL_END);
@@ -386,10 +387,15 @@
 	 * release indication from the BTS or just take it down (e.g.
 	 * on assignment requests)
 	 */
-	if (sach_deact)
+	if (sacch_deact) {
 		gsm48_send_rr_release(lchan);
-	else
+
+		/* Deactivate the SACCH on the BTS side */
+		rsl_deact_sacch(lchan);
+		rsl_start_t3109(lchan);
+	} else {
 		rsl_release_request(lchan, 0, mode);
+	}
 }
 
 /* Consider releasing the channel now */
diff --git a/openbsc/src/libbsc/gsm_04_08_utils.c b/openbsc/src/libbsc/gsm_04_08_utils.c
index 968e62e..de596de 100644
--- a/openbsc/src/libbsc/gsm_04_08_utils.c
+++ b/openbsc/src/libbsc/gsm_04_08_utils.c
@@ -231,11 +231,7 @@
 		lchan->nr, lchan->type);
 
 	/* Send actual release request to MS */
-	gsm48_sendmsg(msg);
-	/* FIXME: Start Timer T3109 */
-
-	/* Deactivate the SACCH on the BTS side */
-	return rsl_deact_sacch(lchan);
+	return gsm48_sendmsg(msg);
 }
 
 int send_siemens_mrpci(struct gsm_lchan *lchan,