diff --git a/server/jetstream_cluster_test.go b/server/jetstream_cluster_test.go
index 40708337..2908c1b8 100644
--- a/server/jetstream_cluster_test.go
+++ b/server/jetstream_cluster_test.go
@@ -5818,8 +5818,8 @@ func TestJetStreamClusterSingleLeafNodeWithoutSharedSystemAccount(t *testing.T)
 
 	// Make sure we can add a stream, etc.
 	si, err = js.AddStream(&nats.StreamConfig{
-		Name:     "TEST",
-		Subjects: []string{"foo"},
+		Name:     "TEST22",
+		Subjects: []string{"bar"},
 		Replicas: 2,
 	})
 	if err != nil {
@@ -5829,6 +5829,73 @@ func TestJetStreamClusterSingleLeafNodeWithoutSharedSystemAccount(t *testing.T)
 		t.Fatalf("Expected stream to be placed in the \"HUB\"")
 	}
 
+	jsLocal, err := nc.JetStream()
+	if err != nil {
+		t.Fatalf("Unexpected error getting JetStream context: %v", err)
+	}
+
+	// Create a mirror on the local leafnode for stream TEST22.
+	_, err = jsLocal.AddStream(&nats.StreamConfig{
+		Name: "M",
+		Mirror: &nats.StreamSource{
+			Name:     "TEST22",
+			External: &nats.ExternalStream{APIPrefix: "$JS.HUB.API"},
+		},
+	})
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+
+	// Publish a message to the HUB's TEST22 stream.
+	if _, err := js.Publish("bar", []byte("OK")); err != nil {
+		t.Fatalf("Unexpected publish error: %v", err)
+	}
+	// Make sure the message arrives in our mirror.
+	checkFor(t, 2*time.Second, 100*time.Millisecond, func() error {
+		si, err := jsLocal.StreamInfo("M")
+		if err != nil {
+			return fmt.Errorf("Could not get stream info: %v", err)
+		}
+		if si.State.Msgs != 1 {
+			return fmt.Errorf("Expected 1 msg, got state: %+v", si.State)
+		}
+		return nil
+	})
+
+	// Now do the reverse and create a sourced stream in the HUB from our local stream on leafnode.
+	// Inside the HUB we need to be able to find our local leafnode JetStream assets, so we need
+	// a mapping in the LN server to allow this to work. Normally this will just be in server config.
+	acc, err := ln.LookupAccount("JSY")
+	if err != nil {
+		c.t.Fatalf("Unexpected error on %v: %v", ln, err)
+	}
+	if err := acc.AddMapping("$JS.LN.API.>", "$JS.API.>"); err != nil {
+		c.t.Fatalf("Error adding mapping: %v", err)
+	}
+
+	// js is the HUB JetStream context here.
+	_, err = js.AddStream(&nats.StreamConfig{
+		Name: "S",
+		Sources: []*nats.StreamSource{{
+			Name:     "M",
+			External: &nats.ExternalStream{APIPrefix: "$JS.LN.API"},
+		}},
+	})
+	if err != nil {
+		t.Fatalf("Unexpected error: %v", err)
+	}
+
+	// Make sure the message arrives in our sourced stream.
+	checkFor(t, 2*time.Second, 100*time.Millisecond, func() error {
+		si, err := js.StreamInfo("S")
+		if err != nil {
+			return fmt.Errorf("Could not get stream info: %v", err)
+		}
+		if si.State.Msgs != 1 {
+			return fmt.Errorf("Expected 1 msg, got state: %+v", si.State)
+		}
+		return nil
+	})
 }
 
 func TestJetStreamClusterLeafDifferentAccounts(t *testing.T) {
diff --git a/server/stream.go b/server/stream.go
index f2ee192d..38a940ac 100644
--- a/server/stream.go
+++ b/server/stream.go
@@ -1387,7 +1387,7 @@ func (mset *stream) setupMirrorConsumer() error {
 	var deliverSubject string
 	ext := mset.cfg.Mirror.External
 
-	if ext != nil {
+	if ext != nil && ext.DeliverPrefix != _EMPTY_ {
 		deliverSubject = strings.ReplaceAll(ext.DeliverPrefix+syncSubject(".M"), "..", ".")
 	} else {
 		deliverSubject = syncSubject("$JS.M")
@@ -1594,7 +1594,7 @@ func (mset *stream) setSourceConsumer(sname string, seq uint64) {
 	var deliverSubject string
 	ext := ssi.External
 
-	if ext != nil {
+	if ext != nil && ext.DeliverPrefix != _EMPTY_ {
 		deliverSubject = strings.ReplaceAll(ext.DeliverPrefix+syncSubject(".S"), "..", ".")
 	} else {
 		deliverSubject = syncSubject("$JS.S")