diff --git a/router/java/src/net/i2p/router/transport/TransportImpl.java b/router/java/src/net/i2p/router/transport/TransportImpl.java
index 2dbd9af3a9..e6e3c80e50 100644
--- a/router/java/src/net/i2p/router/transport/TransportImpl.java
+++ b/router/java/src/net/i2p/router/transport/TransportImpl.java
@@ -559,6 +559,7 @@ public abstract class TransportImpl implements Transport {
             if ((addr[0]&0xFF) >= 224) return false; // no multicast
             if ((addr[0]&0xFF) == 0) return false;
             if ( ((addr[0]&0xFF) == 169) && ((addr[1]&0xFF) == 254) ) return false;
+            if ((addr[0]&0xFF) == 5) return false;  // Hamachi
             return true; // or at least possible to be true
         } else if (addr.length == 16) {
             return false;