diff --git a/libs/openzap/mod_openzap/mod_openzap.c b/libs/openzap/mod_openzap/mod_openzap.c
index c74d8640bd..b8ca4fe71a 100644
--- a/libs/openzap/mod_openzap/mod_openzap.c
+++ b/libs/openzap/mod_openzap/mod_openzap.c
@@ -846,7 +846,6 @@ static switch_status_t channel_receive_message_b(switch_core_session_t *session,
         return SWITCH_STATUS_FALSE;
     }
 
-	zap_mutex_lock(tech_pvt->zchan->mutex);	
 	if (tech_pvt->zchan->state == ZAP_CHANNEL_STATE_TERMINATING) {
 		zap_mutex_unlock(tech_pvt->zchan->mutex);	
 		return SWITCH_STATUS_SUCCESS;
@@ -902,7 +901,6 @@ static switch_status_t channel_receive_message_b(switch_core_session_t *session,
 		break;
 	}
 
-	zap_mutex_unlock(tech_pvt->zchan->mutex);	
 	return SWITCH_STATUS_SUCCESS;
 }
 
@@ -992,12 +990,26 @@ static switch_status_t channel_receive_message(switch_core_session_t *session, s
 	switch_status_t status;
 	switch_channel_t *channel;
 	const char *var;
+	zap_channel_t *zchan = NULL;
 
 	tech_pvt = (private_t *) switch_core_session_get_private(session);
 	assert(tech_pvt != NULL);
 
 	channel = switch_core_session_get_channel(session);
 
+	if (!(zchan = tech_pvt->zchan)) {
+        switch_channel_hangup(channel, SWITCH_CAUSE_LOSE_RACE);
+        return SWITCH_STATUS_FALSE;
+    }
+
+	zap_mutex_lock(zchan->mutex);	
+
+	if (!tech_pvt->zchan) {
+		switch_channel_hangup(channel, SWITCH_CAUSE_LOSE_RACE);
+		status = SWITCH_STATUS_FALSE;
+		goto end;
+	}
+
 	switch (msg->message_id) {
 	case SWITCH_MESSAGE_INDICATE_PROGRESS:
 	case SWITCH_MESSAGE_INDICATE_ANSWER:
@@ -1038,6 +1050,10 @@ static switch_status_t channel_receive_message(switch_core_session_t *session, s
 		break;
 	}
 
+ end:
+
+	zap_mutex_unlock(zchan->mutex);	
+
 	return status;
 
 }
diff --git a/libs/openzap/src/include/openzap.h b/libs/openzap/src/include/openzap.h
index c45aaf911a..2a654f2406 100644
--- a/libs/openzap/src/include/openzap.h
+++ b/libs/openzap/src/include/openzap.h
@@ -567,6 +567,7 @@ struct zap_span {
 	zap_analog_start_type_t start_type;
 	zap_signal_type_t signal_type;
 	void *signal_data;
+	zio_signal_cb_t signal_cb;
 	zap_event_t event_header;
 	char last_error[256];
 	char tone_map[ZAP_TONEMAP_INVALID+1][ZAP_TONEMAP_LEN];
@@ -692,6 +693,7 @@ OZ_DECLARE(zap_status_t) zap_unload_modules(void);
 OZ_DECLARE(zap_status_t) zap_configure_span(const char *type, zap_span_t *span, zio_signal_cb_t sig_cb, ...);
 OZ_DECLARE(zap_status_t) zap_span_start(zap_span_t *span);
 OZ_DECLARE(zap_status_t) zap_span_stop(zap_span_t *span);
+OZ_DECLARE(zap_status_t) zap_span_send_signal(zap_span_t *span, zap_sigmsg_t *sigmsg);
 OZ_DECLARE(int) zap_load_module(const char *name);
 OZ_DECLARE(int) zap_load_module_assume(const char *name);
 OZ_DECLARE(zap_status_t) zap_span_find_by_name(const char *name, zap_span_t **span);
diff --git a/libs/openzap/src/ozmod/ozmod_analog/ozmod_analog.c b/libs/openzap/src/ozmod/ozmod_analog/ozmod_analog.c
index 3978c94106..595f0ecebc 100644
--- a/libs/openzap/src/ozmod/ozmod_analog/ozmod_analog.c
+++ b/libs/openzap/src/ozmod/ozmod_analog/ozmod_analog.c
@@ -176,7 +176,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_analog_configure_span)
 	analog_data->flags = flags;
 	analog_data->digit_timeout = digit_timeout;
 	analog_data->max_dialstr = max_dialstr;
-	analog_data->sig_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	strncpy(analog_data->hotline, hotline, sizeof(analog_data->hotline));
 	span->signal_type = ZAP_SIGTYPE_ANALOG;
 	span->signal_data = analog_data;
@@ -481,7 +481,7 @@ static void *zap_analog_channel_run(zap_thread_t *me, void *obj)
 						sig.event_id = ZAP_SIGEVENT_UP;
 					}
 
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					continue;
 				}
 				break;
@@ -501,14 +501,14 @@ static void *zap_analog_channel_run(zap_thread_t *me, void *obj)
 						zap_set_string(zchan->caller_data.dnis.digits, dtmf);
 					}
 
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					continue;
 				}
 				break;
 			case ZAP_CHANNEL_STATE_DOWN:
 				{
 					sig.event_id = ZAP_SIGEVENT_STOP;
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					goto done;
 				}
 				break;
@@ -549,7 +549,7 @@ static void *zap_analog_channel_run(zap_thread_t *me, void *obj)
 					sig.span_id = zchan->span_id;
 					sig.channel = zchan;
 					sig.event_id = ZAP_SIGEVENT_PROGRESS;
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					
 				}
 				break;
@@ -608,7 +608,7 @@ static void *zap_analog_channel_run(zap_thread_t *me, void *obj)
 				last_digit = elapsed;
 				sig.event_id = ZAP_SIGEVENT_COLLECTED_DIGIT;
 				sig.raw_data = dtmf;
-				if (analog_data->sig_cb(&sig) == ZAP_BREAK) {
+				if (zap_span_send_signal(zchan->span, &sig) == ZAP_BREAK) {
 					collecting = 0;
 				}
 			}
@@ -654,9 +654,7 @@ static void *zap_analog_channel_run(zap_thread_t *me, void *obj)
 				if (zchan->detected_tones[i]) {
 					zap_log(ZAP_LOG_DEBUG, "Detected tone %s on %d:%d\n", zap_tonemap2str(i), zchan->span_id, zchan->chan_id);
 					sig.raw_data = &i;
-					if (analog_data->sig_cb) {
-						analog_data->sig_cb(&sig);
-					}
+					zap_span_send_signal(zchan->span, &sig);
 				}
 			}
 			
@@ -843,7 +841,7 @@ static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *even
 				zap_set_state_locked(event->channel,  ZAP_CHANNEL_STATE_UP);
 			} else {
 				sig.event_id = ZAP_SIGEVENT_FLASH;
-				analog_data->sig_cb(&sig);
+				zap_span_send_signal(span, &sig);
 			}
 		}
 		break;
diff --git a/libs/openzap/src/ozmod/ozmod_analog/zap_analog.h b/libs/openzap/src/ozmod/ozmod_analog/zap_analog.h
index 563285eb2c..3ffa422ead 100644
--- a/libs/openzap/src/ozmod/ozmod_analog/zap_analog.h
+++ b/libs/openzap/src/ozmod/ozmod_analog/zap_analog.h
@@ -48,7 +48,6 @@ struct zap_analog_data {
 	uint32_t max_dialstr;
 	uint32_t digit_timeout;
 	char hotline[ZAP_MAX_HOTLINE_STR];
-	zio_signal_cb_t sig_cb;
 };
 
 
diff --git a/libs/openzap/src/ozmod/ozmod_analog_em/ozmod_analog_em.c b/libs/openzap/src/ozmod/ozmod_analog_em/ozmod_analog_em.c
index 4468e4b92d..581c6dd45a 100644
--- a/libs/openzap/src/ozmod/ozmod_analog_em/ozmod_analog_em.c
+++ b/libs/openzap/src/ozmod/ozmod_analog_em/ozmod_analog_em.c
@@ -145,7 +145,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_analog_em_configure_span)
 	span->start = zap_analog_em_start;
 	analog_data->digit_timeout = digit_timeout;
 	analog_data->max_dialstr = max_dialstr;
-	analog_data->sig_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	span->signal_type = ZAP_SIGTYPE_ANALOG;
 	span->signal_data = analog_data;
 	span->outgoing_call = analog_em_outgoing_call;
@@ -349,7 +349,7 @@ static void *zap_analog_em_channel_run(zap_thread_t *me, void *obj)
 
 					sig.event_id = ZAP_SIGEVENT_UP;
 
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					continue;
 				}
 				break;
@@ -370,14 +370,14 @@ static void *zap_analog_em_channel_run(zap_thread_t *me, void *obj)
 
 					sig.event_id = ZAP_SIGEVENT_START;
 
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					continue;
 				}
 				break;
 			case ZAP_CHANNEL_STATE_DOWN:
 				{
 					sig.event_id = ZAP_SIGEVENT_STOP;
-					analog_data->sig_cb(&sig);
+					zap_span_send_signal(zchan->span, &sig);
 					goto done;
 				}
 				break;
@@ -440,7 +440,7 @@ static void *zap_analog_em_channel_run(zap_thread_t *me, void *obj)
 				last_digit = elapsed;
 				sig.event_id = ZAP_SIGEVENT_COLLECTED_DIGIT;
 				sig.raw_data = dtmf;
-				if (analog_data->sig_cb(&sig) == ZAP_BREAK) {
+				if (zap_span_send_signal(zchan->span, &sig) == ZAP_BREAK) {
 					collecting = 0;
 				}
 			}
@@ -480,9 +480,7 @@ static void *zap_analog_em_channel_run(zap_thread_t *me, void *obj)
 				if (zchan->detected_tones[i]) {
 					zap_log(ZAP_LOG_DEBUG, "Detected tone %s on %d:%d\n", zap_tonemap2str(i), zchan->span_id, zchan->chan_id);
 					sig.raw_data = &i;
-					if (analog_data->sig_cb) {
-						analog_data->sig_cb(&sig);
-					}
+					zap_span_send_signal(zchan->span, &sig);
 				}
 			}
 			
diff --git a/libs/openzap/src/ozmod/ozmod_analog_em/zap_analog_em.h b/libs/openzap/src/ozmod/ozmod_analog_em/zap_analog_em.h
index 5f0f726063..eb9f9f3d20 100644
--- a/libs/openzap/src/ozmod/ozmod_analog_em/zap_analog_em.h
+++ b/libs/openzap/src/ozmod/ozmod_analog_em/zap_analog_em.h
@@ -51,7 +51,6 @@ struct zap_analog_data {
 	uint32_t flags;
 	uint32_t max_dialstr;
 	uint32_t digit_timeout;
-	zio_signal_cb_t sig_cb;
 };
 
 static void *zap_analog_em_run(zap_thread_t *me, void *obj);
diff --git a/libs/openzap/src/ozmod/ozmod_isdn/ozmod_isdn.c b/libs/openzap/src/ozmod/ozmod_isdn/ozmod_isdn.c
index e4e9a1511f..3c061960a1 100644
--- a/libs/openzap/src/ozmod/ozmod_isdn/ozmod_isdn.c
+++ b/libs/openzap/src/ozmod/ozmod_isdn/ozmod_isdn.c
@@ -699,7 +699,7 @@ static L3INT zap_isdn_931_34(void *pvt, L2UCHAR *msg, L2INT mlen)
 						sig.channel->caller_data.hangup_cause = (cause) ? cause->Value : ZAP_CAUSE_NORMAL_UNSPECIFIED;
 
 						sig.event_id = ZAP_SIGEVENT_STOP;
-						status = isdn_data->sig_cb(&sig);
+						status = zap_span_send_signal(zchan->span, &sig);
 
 						zap_log(ZAP_LOG_DEBUG, "Received %s in state %s, requested hangup for channel %d:%d\n", what, zap_channel_state2str(zchan->state), zchan->span_id, chan_id);
 					}
@@ -1186,7 +1186,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1230,7 +1230,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (!zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_START;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			}
@@ -1240,7 +1240,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			zchan->caller_data.hangup_cause = ZAP_CAUSE_NORMAL_UNSPECIFIED;
 			sig.event_id = ZAP_SIGEVENT_RESTART;
-			status = isdn_data->sig_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_DOWN);
 		}
 		break;
@@ -1248,7 +1248,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS_MEDIA;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1268,7 +1268,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_UP;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1473,7 +1473,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 			zap_log(ZAP_LOG_DEBUG, "Terminating: Direction %s\n", zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND) ? "Outbound" : "Inbound");
 
 			sig.event_id = ZAP_SIGEVENT_STOP;
-			status = isdn_data->sig_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			gen->MesType = Q931mes_RELEASE;
 			gen->CRVFlag = zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND) ? 0 : 1;
 			Q931Rx43(&isdn_data->q931, (void *)gen, gen->Size);
@@ -1513,7 +1513,6 @@ static __inline__ void check_state(zap_span_t *span)
 static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *event)
 {
 	zap_sigmsg_t sig;
-	zap_isdn_data_t *isdn_data = span->signal_data;
 
 	memset(&sig, 0, sizeof(sig));
 	sig.chan_id = event->channel->chan_id;
@@ -1538,7 +1537,7 @@ static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *even
 
 			
 			zap_channel_get_alarms(event->channel);
-			isdn_data->sig_cb(&sig);
+			zap_span_send_signal(span, &sig);
 			zap_log(ZAP_LOG_WARNING, "channel %d:%d (%d:%d) has alarms! [%s]\n", 
 					event->channel->span_id, event->channel->chan_id, 
 					event->channel->physical_span_id, event->channel->physical_chan_id, 
@@ -1554,7 +1553,7 @@ static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *even
 			sig.event_id = ZAP_OOB_ALARM_CLEAR;
 			zap_clear_flag(event->channel, ZAP_CHANNEL_SUSPENDED);
 			zap_channel_get_alarms(event->channel);
-			isdn_data->sig_cb(&sig);
+			zap_span_send_signal(span, &sig);
 		}
 		break;
 	}
@@ -2355,7 +2354,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_isdn_configure_span)
 					
 	span->start = zap_isdn_start;
 	span->stop = zap_isdn_stop;
-	isdn_data->sig_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	isdn_data->dchans[0] = dchans[0];
 	isdn_data->dchans[1] = dchans[1];
 	isdn_data->dchan = isdn_data->dchans[0];
diff --git a/libs/openzap/src/ozmod/ozmod_isdn/zap_isdn.h b/libs/openzap/src/ozmod/ozmod_isdn/zap_isdn.h
index b16b004a9d..c5e0e5a711 100644
--- a/libs/openzap/src/ozmod/ozmod_isdn/zap_isdn.h
+++ b/libs/openzap/src/ozmod/ozmod_isdn/zap_isdn.h
@@ -60,7 +60,6 @@ struct zap_isdn_data {
 	zap_channel_t *dchan;
 	zap_channel_t *dchans[2];
 	struct zap_sigmsg sigmsg;
-	zio_signal_cb_t sig_cb;
 	uint32_t flags;
 	int32_t mode;
 	int32_t digit_timeout;
diff --git a/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.c b/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.c
index a8e3fea6f7..0c8aadede3 100644
--- a/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.c
+++ b/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.c
@@ -454,7 +454,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else if (call) {
@@ -468,7 +468,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS_MEDIA;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else if (call) {
@@ -484,7 +484,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 				if (call) {
 					pri_acknowledge(isdn_data->spri.pri, call, zchan->chan_id, 0);
 					sig.event_id = ZAP_SIGEVENT_START;
-					if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+					if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 						zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 					}
 				} else {
@@ -497,7 +497,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			zchan->caller_data.hangup_cause = ZAP_CAUSE_NORMAL_UNSPECIFIED;
 			sig.event_id = ZAP_SIGEVENT_RESTART;
-			status = isdn_data->sig_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_DOWN);
 		}
 		break;
@@ -505,7 +505,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_UP;
-				if ((status = isdn_data->sig_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else if (call) {
@@ -579,7 +579,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 	case ZAP_CHANNEL_STATE_TERMINATING:
 		{
 			sig.event_id = ZAP_SIGEVENT_STOP;
-			status = isdn_data->sig_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_DOWN);
 
 		}
@@ -807,7 +807,6 @@ static int on_ring(lpwrap_pri_t *spri, lpwrap_pri_event_t event_type, pri_event
 static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *event)
 {
 	zap_sigmsg_t sig;
-	zap_libpri_data_t *isdn_data = span->signal_data;
 
 	memset(&sig, 0, sizeof(sig));
 	sig.chan_id = event->channel->chan_id;
@@ -832,7 +831,7 @@ static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *even
 
 			
 			zap_channel_get_alarms(event->channel);
-			isdn_data->sig_cb(&sig);
+			zap_span_send_signal(span, &sig);
 			zap_log(ZAP_LOG_WARNING, "channel %d:%d (%d:%d) has alarms! [%s]\n", 
 					event->channel->span_id, event->channel->chan_id, 
 					event->channel->physical_span_id, event->channel->physical_chan_id, 
@@ -848,7 +847,7 @@ static __inline__ zap_status_t process_event(zap_span_t *span, zap_event_t *even
 			sig.event_id = ZAP_OOB_ALARM_CLEAR;
 			zap_clear_flag(event->channel, ZAP_CHANNEL_SUSPENDED);
 			zap_channel_get_alarms(event->channel);
-			isdn_data->sig_cb(&sig);
+			zap_span_send_signal(span, &sig);
 		}
 		break;
 	}
@@ -1329,7 +1328,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_libpri_configure_span)
     
 	span->start = zap_libpri_start;
 	span->stop = zap_libpri_stop;
-	isdn_data->sig_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	//isdn_data->dchans[0] = dchans[0];
 	//isdn_data->dchans[1] = dchans[1];
 	//isdn_data->dchan = isdn_data->dchans[0];
diff --git a/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.h b/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.h
index 4e33aba17d..8c929516ba 100644
--- a/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.h
+++ b/libs/openzap/src/ozmod/ozmod_libpri/ozmod_libpri.h
@@ -55,7 +55,6 @@ struct zap_libpri_data {
 	zap_channel_t *dchan;
 	zap_channel_t *dchans[2];
 	struct zap_sigmsg sigmsg;
-	zio_signal_cb_t sig_cb;
 	uint32_t flags;
 	int32_t mode;
 	zap_isdn_opts_t opts;
diff --git a/libs/openzap/src/ozmod/ozmod_r2/ozmod_r2.c b/libs/openzap/src/ozmod/ozmod_r2/ozmod_r2.c
index f911e67d95..a8c8abf0fc 100644
--- a/libs/openzap/src/ozmod/ozmod_r2/ozmod_r2.c
+++ b/libs/openzap/src/ozmod/ozmod_r2/ozmod_r2.c
@@ -91,8 +91,6 @@ typedef struct oz_r2_conf_s {
 
 /* r2 configuration stored in span->signal_data */
 typedef struct zap_r2_data_s {
-	/* signaling callback */
-	zio_signal_cb_t sig_cb;
 	/* span flags */
 	zap_r2_flag_t flags;
 	/* openr2 handle for the R2 variant context */
@@ -254,7 +252,7 @@ static void zap_r2_on_call_offered(openr2_chan_t *r2chan, const char *ani, const
 	sigev.channel = zchan;
 	sigev.event_id = ZAP_SIGEVENT_START;
 
-	if (r2data->sig_cb(&sigev) != ZAP_SUCCESS) {
+	if (zap_span_send_signal(zchan->span, &sigev) != ZAP_SUCCESS) {
 		zap_log(ZAP_LOG_NOTICE, "Failed to handle call offered on chan %d\n", openr2_chan_get_number(r2chan));
 		openr2_chan_disconnect_call(r2chan, OR2_CAUSE_OUT_OF_ORDER);
 		zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_CANCEL);
@@ -324,7 +322,7 @@ static void zap_r2_on_call_disconnect(openr2_chan_t *r2chan, openr2_call_disconn
 	sigev.event_id = ZAP_SIGEVENT_STOP;
 	r2data = zchan->span->signal_data;
 
-	r2data->sig_cb(&sigev);
+	zap_span_send_signal(zchan->span, &sigev);
 }
 
 static void zap_r2_on_call_end(openr2_chan_t *r2chan)
@@ -378,7 +376,7 @@ static void zap_r2_on_protocol_error(openr2_chan_t *r2chan, openr2_protocol_erro
 	sigev.event_id = ZAP_SIGEVENT_STOP;
 	r2data = zchan->span->signal_data;
 
-	r2data->sig_cb(&sigev);
+	zap_span_send_signal(zchan->span, &sigev);
 }
 
 static void zap_r2_on_line_blocked(openr2_chan_t *r2chan)
@@ -461,7 +459,7 @@ static int zap_r2_on_dnis_digit_received(openr2_chan_t *r2chan, char digit)
 	sigev.channel = zchan;
 	sigev.event_id = ZAP_SIGEVENT_COLLECTED_DIGIT;
 	r2data = zchan->span->signal_data;
-	if (r2data->sig_cb(&sigev) == ZAP_BREAK) {
+	if (zap_span_send_signal(zchan->span, &sigev) == ZAP_BREAK) {
 		zap_log(ZAP_LOG_NOTICE, "Requested to stop getting DNIS. Current DNIS = %s on chan %d\n", zchan->caller_data.dnis.digits, openr2_chan_get_number(r2chan));
 		return OR2_STOP_DNIS_REQUEST; 
 	}
@@ -885,7 +883,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_r2_configure_span)
 
 	span->start = zap_r2_start;
 	r2data->flags = 0;
-	r2data->sig_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	span->signal_type = ZAP_SIGTYPE_R2;
 	span->signal_data = r2data;
 	span->outgoing_call = r2_outgoing_call;
@@ -1005,7 +1003,7 @@ static void *zap_r2_channel_run(zap_thread_t *me, void *obj)
 						} else {
 							zap_log(ZAP_LOG_DEBUG, "PROGRESS: Notifying progress in channel %d\n", zchan->physical_chan_id);
 							sigev.event_id = ZAP_SIGEVENT_PROGRESS;
-							if (r2data->sig_cb(&sigev) != ZAP_SUCCESS) {
+							if (zap_span_send_signal(zchan->span, &sigev) != ZAP_SUCCESS) {
 								zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 							}
 						}
@@ -1028,7 +1026,7 @@ static void *zap_r2_channel_run(zap_thread_t *me, void *obj)
 						} else {
 							zap_log(ZAP_LOG_DEBUG, "UP: Notifying of call answered in channel %d\n", zchan->physical_chan_id);
 							sigev.event_id = ZAP_SIGEVENT_UP;
-							if (r2data->sig_cb(&sigev) != ZAP_SUCCESS) {
+							if (zap_span_send_signal(zchan->span, &sigev) != ZAP_SUCCESS) {
 								zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 							}
 						}
diff --git a/libs/openzap/src/ozmod/ozmod_sangoma_boost/ozmod_sangoma_boost.c b/libs/openzap/src/ozmod/ozmod_sangoma_boost/ozmod_sangoma_boost.c
index ffbc4c8d33..9b97c93803 100644
--- a/libs/openzap/src/ozmod/ozmod_sangoma_boost/ozmod_sangoma_boost.c
+++ b/libs/openzap/src/ozmod/ozmod_sangoma_boost/ozmod_sangoma_boost.c
@@ -996,7 +996,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS_MEDIA;
-				if ((status = sangoma_boost_data->signal_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1017,7 +1017,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_PROGRESS;
-				if ((status = sangoma_boost_data->signal_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1042,7 +1042,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (!zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_START;
-				if ((status = sangoma_boost_data->signal_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			}
@@ -1051,7 +1051,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 	case ZAP_CHANNEL_STATE_RESTART:
 		{
 			sig.event_id = ZAP_SIGEVENT_RESTART;
-			status = sangoma_boost_data->signal_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			zap_set_sflag_locked(zchan, SFLAG_SENT_FINAL_MSG);
 			zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_DOWN);
 		}
@@ -1060,7 +1060,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			if (zap_test_flag(zchan, ZAP_CHANNEL_OUTBOUND)) {
 				sig.event_id = ZAP_SIGEVENT_UP;
-				if ((status = sangoma_boost_data->signal_cb(&sig) != ZAP_SUCCESS)) {
+				if ((status = zap_span_send_signal(zchan->span, &sig) != ZAP_SUCCESS)) {
 					zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP);
 				}
 			} else {
@@ -1125,7 +1125,7 @@ static __inline__ void state_advance(zap_channel_t *zchan)
 		{
 			zap_set_sflag_locked(zchan, SFLAG_TERMINATING);
 			sig.event_id = ZAP_SIGEVENT_STOP;
-			status = sangoma_boost_data->signal_cb(&sig);
+			status = zap_span_send_signal(zchan->span, &sig);
 			zap_set_state_locked(zchan, ZAP_CHANNEL_STATE_HANGUP_COMPLETE);
 		}
 		break;
@@ -1593,7 +1593,7 @@ static ZIO_SIG_CONFIGURE_FUNCTION(zap_sangoma_boost_configure_span)
 	sangoma_boost_data->mcon.cfg.local_port = local_port;
 	zap_set_string(sangoma_boost_data->mcon.cfg.remote_ip, remote_ip);
 	sangoma_boost_data->mcon.cfg.remote_port = remote_port;
-	sangoma_boost_data->signal_cb = sig_cb;
+	span->signal_cb = sig_cb;
 	span->start = zap_sangoma_boost_start;
 	span->signal_data = sangoma_boost_data;
     span->signal_type = ZAP_SIGTYPE_SANGOMABOOST;
diff --git a/libs/openzap/src/ozmod/ozmod_sangoma_boost/zap_sangoma_boost.h b/libs/openzap/src/ozmod/ozmod_sangoma_boost/zap_sangoma_boost.h
index 932787c93a..a48060812b 100644
--- a/libs/openzap/src/ozmod/ozmod_sangoma_boost/zap_sangoma_boost.h
+++ b/libs/openzap/src/ozmod/ozmod_sangoma_boost/zap_sangoma_boost.h
@@ -44,7 +44,6 @@ typedef enum {
 typedef struct zap_sangoma_boost_data {
 	sangomabc_connection_t mcon;
 	sangomabc_connection_t pcon;
-	zio_signal_cb_t signal_cb;
 	uint32_t flags;
 } zap_sangoma_boost_data_t;
 
diff --git a/libs/openzap/src/zap_io.c b/libs/openzap/src/zap_io.c
index 3abae9fea1..4044621825 100644
--- a/libs/openzap/src/zap_io.c
+++ b/libs/openzap/src/zap_io.c
@@ -2735,6 +2735,26 @@ OZ_DECLARE(zap_status_t) zap_span_start(zap_span_t *span)
 	return ZAP_FAIL;
 }
 
+OZ_DECLARE(zap_status_t) zap_span_send_signal(zap_span_t *span, zap_sigmsg_t *sigmsg)
+{
+	zap_status_t status = ZAP_FAIL;
+
+	if (span->signal_cb) {
+
+		if (sigmsg->channel) {
+			zap_mutex_lock(sigmsg->channel->mutex);
+		}
+
+		status = span->signal_cb(sigmsg);
+
+		if (sigmsg->channel) {
+			zap_mutex_unlock(sigmsg->channel->mutex);
+		}
+	}
+
+	return status;
+}
+
 
 OZ_DECLARE(zap_status_t) zap_global_init(void)
 {