diff --git a/emu.c b/emu.c
index 43abf30..1e067f9 100644
--- a/emu.c
+++ b/emu.c
@@ -82,11 +82,14 @@ hook_pre(struct ovni_emu *emu)
 
 	switch(emu->cur_ev->header.model)
 	{
-		case 'O': hook_pre_ovni(emu); break;
-		case 'V': hook_pre_nosv(emu); break;
-		default:
-			  //dbg("unknown model %c\n", emu->cur_ev->model);
+		case 'O': hook_pre_ovni(emu);
 			  break;
+		case 'V': hook_pre_nosv(emu);
+			  break;
+		case '*': hook_pre_nosv(emu);
+			  break;
+		default:
+			break;
 	}
 }
 
@@ -97,8 +100,12 @@ hook_emit(struct ovni_emu *emu)
 
 	switch(emu->cur_ev->header.model)
 	{
-		case 'O': hook_emit_ovni(emu); break;
-		case 'V': hook_emit_nosv(emu); break;
+		case 'O': hook_emit_ovni(emu);
+			  break;
+		case 'V': hook_emit_nosv(emu);
+			  break;
+		case '*': hook_emit_nosv(emu);
+			  break;
 		default:
 			  //dbg("unknown model %c\n", emu->cur_ev->model);
 			  break;
@@ -112,8 +119,12 @@ hook_post(struct ovni_emu *emu)
 
 	switch(emu->cur_ev->header.model)
 	{
-		case 'O': hook_post_ovni(emu); break;
-		case 'V': hook_post_nosv(emu); break;
+		case 'O': hook_post_ovni(emu);
+			  break;
+		case 'V': hook_post_nosv(emu);
+			  break;
+		case '*': hook_post_nosv(emu);
+			  break;
 		default:
 			  //dbg("unknown model %c\n", emu->cur_ev->model);
 			  break;
@@ -143,6 +154,21 @@ next_event(struct ovni_emu *emu)
 
 	trace = &emu->trace;
 
+	/* Look for virtual events first */
+
+	if(trace->ivirtual < trace->nvirtual)
+	{
+		emu->cur_ev = &trace->virtual_events[trace->ivirtual];
+		trace->ivirtual++;
+		return 0;
+	}
+	else
+	{
+		/* Reset virtual events to 0 */
+		trace->ivirtual = 0;
+		trace->nvirtual = 0;
+	}
+
 	f = -1;
 	minclock = 0;
 
@@ -218,8 +244,9 @@ emulate(struct ovni_emu *emu)
 		hook_emit(emu);
 		hook_post(emu);
 
-		/* Read the next event */
-		ovni_load_next_event(emu->cur_stream);
+		/* Read the next event if no virtual events exist */
+		if(emu->trace.ivirtual == emu->trace.nvirtual)
+			ovni_load_next_event(emu->cur_stream);
 	}
 }
 
@@ -587,6 +614,53 @@ write_row_cpu(struct ovni_emu *emu)
 	fclose(f);
 }
 
+static int
+emu_virtual_init(struct ovni_emu *emu)
+{
+	struct ovni_trace *trace;
+
+	trace = &emu->trace;
+
+	trace->ivirtual = 0;
+	trace->nvirtual = 0;
+
+	trace->virtual_events = calloc(MAX_VIRTUAL_EVENTS,
+			sizeof(struct ovni_ev));
+
+	if(trace->virtual_events == NULL)
+	{
+		perror("calloc");
+		exit(EXIT_FAILURE);
+	}
+
+	return 0;
+}
+
+void
+emu_virtual_ev(struct ovni_emu *emu, char *mcv)
+{
+	struct ovni_trace *trace;
+	struct ovni_ev *ev;
+
+	trace = &emu->trace;
+
+	if(trace->nvirtual >= MAX_VIRTUAL_EVENTS)
+	{
+		err("too many virtual events\n");
+		exit(EXIT_FAILURE);
+	}
+
+	ev = &trace->virtual_events[trace->nvirtual];
+
+	ev->header.flags = 0;
+	ev->header.model = mcv[0];
+	ev->header.class = mcv[1];
+	ev->header.value = mcv[2];
+	ev->header.clock = emu->cur_ev->header.clock;
+
+	trace->nvirtual++;
+}
+
 static void
 emu_init(struct ovni_emu *emu, int argc, char *argv[])
 {
@@ -597,6 +671,9 @@ emu_init(struct ovni_emu *emu, int argc, char *argv[])
 	if(ovni_load_trace(&emu->trace, emu->tracedir))
 		abort();
 
+	if(emu_virtual_init(emu))
+		abort();
+
 	if(ovni_load_streams(&emu->trace))
 		abort();
 
diff --git a/emu.h b/emu.h
index 496559a..1a6294c 100644
--- a/emu.h
+++ b/emu.h
@@ -100,6 +100,9 @@ struct ovni_ethread {
 
 	/* nosv task */
 	struct nosv_task *task;
+
+	/* Should we print the subsystem? */
+	int show_ss;
 };
 
 /* State of each emulated process */
@@ -179,9 +182,21 @@ struct ovni_loom {
 	struct ovni_eproc proc[OVNI_MAX_PROC];
 };
 
+#define MAX_VIRTUAL_EVENTS 16
+
 struct ovni_trace {
 	int nlooms;
 	struct ovni_loom loom[OVNI_MAX_LOOM];
+
+	/* Index of next virtual event */
+	int ivirtual;
+
+	/* Number of virtual events stored */
+	int nvirtual;
+
+	/* The virtual events are generated by the emulator */
+	struct ovni_ev *virtual_events;
+
 	int nstreams;
 	struct ovni_stream *stream;
 };
@@ -254,4 +269,7 @@ struct ovni_ethread *emu_get_thread(struct ovni_eproc *proc, int tid);
 
 void emu_emit_prv(struct ovni_emu *emu, int type, int val);
 
+void
+emu_virtual_ev(struct ovni_emu *emu, char *mcv);
+
 #endif /* OVNI_EMU_H */
diff --git a/emu_nosv.c b/emu_nosv.c
index 8e62240..a5d36bb 100644
--- a/emu_nosv.c
+++ b/emu_nosv.c
@@ -146,7 +146,6 @@ pre_task_end(struct ovni_emu *emu)
 	dbg("task id=%d ends\n", task->id);
 }
 
-
 static void
 pre_task(struct ovni_emu *emu)
 {
@@ -221,16 +220,23 @@ pre_type(struct ovni_emu *emu)
 	}
 }
 
-
 void
 hook_pre_nosv(struct ovni_emu *emu)
 {
-	switch(emu->cur_ev->header.class)
+	switch(emu->cur_ev->header.model)
 	{
-		case 'T': pre_task(emu); break;
-		case 'Y': pre_type(emu); break;
+		/* Only listen for nosv events */
+		case 'V':
+			switch(emu->cur_ev->header.class)
+			{
+				case 'T': pre_task(emu); break;
+				case 'Y': pre_type(emu); break;
+				default:
+					break;
+			}
+			break;
 		default:
-			  break;
+			break;
 	}
 
 	hook_pre_nosv_ss(emu);
diff --git a/emu_nosv_ss.c b/emu_nosv_ss.c
index f83955f..1ae889e 100644
--- a/emu_nosv_ss.c
+++ b/emu_nosv_ss.c
@@ -19,6 +19,7 @@ static void
 ss_init(struct ovni_ethread *t)
 {
 	t->nss = 0;
+	t->show_ss = 0;
 }
 
 static void
@@ -134,16 +135,58 @@ pre_memory(struct ovni_emu *emu)
 	}
 }
 
+/* Hook for the virtual "thread changed" event */
+static void
+pre_thread_change(struct ovni_emu *emu)
+{
+	struct ovni_ethread *th;
+
+	th = emu->cur_thread;
+
+	/* Only print the subsystem if the thread is running */
+	if(th->state == TH_ST_RUNNING)
+		th->show_ss = 1;
+	else
+		th->show_ss = 0;
+}
+
+static void
+pre_thread(struct ovni_emu *emu)
+{
+	switch(emu->cur_ev->header.value)
+	{
+		case 'c': pre_thread_change(emu); break;
+		default:
+			break;
+	}
+}
+
 void
 hook_pre_nosv_ss(struct ovni_emu *emu)
 {
-	switch(emu->cur_ev->header.class)
+	switch(emu->cur_ev->header.model)
 	{
-		case 'S': pre_sched(emu); break;
-		case 'U': pre_submit(emu); break;
-		case 'M': pre_memory(emu); break;
+		/* Listen for virtual events as well */
+		case '*':
+			switch(emu->cur_ev->header.class)
+			{
+				case 'H': pre_thread(emu); break;
+				default:
+					break;
+			}
+			break;
+		case 'V':
+			switch(emu->cur_ev->header.class)
+			{
+				case 'S': pre_sched(emu); break;
+				case 'U': pre_submit(emu); break;
+				case 'M': pre_memory(emu); break;
+				default:
+					break;
+			}
+			break;
 		default:
-			  break;
+			break;
 	}
 }
 
@@ -187,6 +230,12 @@ hook_emit_nosv_ss(struct ovni_emu *emu)
 
 	th = emu->cur_thread;
 
+	if(th->show_ss == 0)
+	{
+		emit_thread_state(emu, th, PTT_SUBSYSTEM, ST_NULL);
+		return;
+	}
+
 	/* Only emit a state if needed */
 	if(th->ss_event != EV_NULL)
 	{
diff --git a/emu_ovni.c b/emu_ovni.c
index 8af7c11..32bc1c7 100644
--- a/emu_ovni.c
+++ b/emu_ovni.c
@@ -174,8 +174,14 @@ ev_thread(struct ovni_emu *emu)
 		case 'p': ev_thread_pause(emu); break;
 		case 'r': ev_thread_resume(emu); break;
 		default:
-			break;
+			  err("unknown thread event value %c\n",
+					  ev->header.value);
+			  exit(EXIT_FAILURE);
 	}
+
+	/* All events change the thread state: inject a virtual event to
+	 * notify other modules */
+	emu_virtual_ev(emu, "*Hc");
 }
 
 static void