diff --git a/whisper/peer_test.go b/whisper/peer_test.go
index 594671ee14c80a26eac49be83c598b3e82f45684..b3d2031c194694c7eff7d56bb382d67a703083e1 100644
--- a/whisper/peer_test.go
+++ b/whisper/peer_test.go
@@ -239,14 +239,17 @@ func TestPeerMessageExpiration(t *testing.T) {
 	}
 	payload := []interface{}{envelope}
 	if err := p2p.ExpectMsg(tester.stream, messagesCode, payload); err != nil {
-		t.Fatalf("message mismatch: %v", err)
+		// A premature empty message may have been broadcast, check the next too
+		if err := p2p.ExpectMsg(tester.stream, messagesCode, payload); err != nil {
+			t.Fatalf("message mismatch: %v", err)
+		}
 	}
 	// Check that the message is inside the cache
 	if !peer.known.Has(envelope.Hash()) {
 		t.Fatalf("message not found in cache")
 	}
 	// Discard messages until expiration and check cache again
-	exp := time.Now().Add(time.Second + expirationCycle)
+	exp := time.Now().Add(time.Second + 2*expirationCycle + 100*time.Millisecond)
 	for time.Now().Before(exp) {
 		if err := p2p.ExpectMsg(tester.stream, messagesCode, []interface{}{}); err != nil {
 			t.Fatalf("message mismatch: %v", err)
diff --git a/whisper/whisper.go b/whisper/whisper.go
index 676d8ae7a3c5eccf37ab40ec9482df3b7f4aaa0b..a341f23e48b63ae8ef24e1229437e20de21ad9c4 100644
--- a/whisper/whisper.go
+++ b/whisper/whisper.go
@@ -234,6 +234,11 @@ func (self *Whisper) add(envelope *Envelope) error {
 	self.poolMu.Lock()
 	defer self.poolMu.Unlock()
 
+	// short circuit when a received envelope has already expired
+	if envelope.Expiry <= uint32(time.Now().Unix()) {
+		return nil
+	}
+
 	// Insert the message into the tracked pool
 	hash := envelope.Hash()
 	if _, ok := self.messages[hash]; ok {
diff --git a/whisper/whisper_test.go b/whisper/whisper_test.go
index 1a9a8667ada53687cfb9e58e8670b6f9740c8265..b83ce0fe7026c332d6d61cd6c329f7d57472c2c3 100644
--- a/whisper/whisper_test.go
+++ b/whisper/whisper_test.go
@@ -207,4 +207,13 @@ func TestMessageExpiration(t *testing.T) {
 	if found {
 		t.Fatalf("message not expired from cache")
 	}
+
+	node.add(envelope)
+	node.poolMu.RLock()
+	_, found = node.messages[envelope.Hash()]
+	node.poolMu.RUnlock()
+	if found {
+		t.Fatalf("message was added to cache")
+	}
+
 }