diff --git a/whisper/whisperv6/message_test.go b/whisper/whisperv6/message_test.go
index f8e61c31ab..884bc71d76 100644
--- a/whisper/whisperv6/message_test.go
+++ b/whisper/whisperv6/message_test.go
@@ -465,6 +465,6 @@ func TestAesNonce(t *testing.T) {
 	// This is the most important single test in this package.
 	// If it fails, whisper will not be working.
 	if aesgcm.NonceSize() != aesNonceLength {
-		t.Fatalf("Nonce size is wrong. This is a critical error. Apparently AES nonce size have changed in the new version of AES GCM package. Whisper will not be working untill this problem is resolved.")
+		t.Fatalf("Nonce size is wrong. This is a critical error. Apparently AES nonce size have changed in the new version of AES GCM package. Whisper will not be working until this problem is resolved.")
 	}
 }
diff --git a/whisper/whisperv6/whisper.go b/whisper/whisperv6/whisper.go
index f7d71f612d..859546c671 100644
--- a/whisper/whisperv6/whisper.go
+++ b/whisper/whisperv6/whisper.go
@@ -984,7 +984,13 @@ func validatePrivateKey(k *ecdsa.PrivateKey) bool {
 // validateSymmetricKey returns false if the key contains all zeros,
 // which is a simplest and the most common bug.
 func validateRandomData(k []byte, expectedSize int) bool {
-	return len(k) == expectedSize && !containsOnlyZeros(k)
+	if len(k) != expectedSize {
+		return false
+	}
+	if expectedSize > 4 && containsOnlyZeros(k) {
+		return false
+	}
+	return true
 }
 
 // containsOnlyZeros checks if the data contain only zeros.