diff --git a/router/java/src/net/i2p/router/transport/TransportUtil.java b/router/java/src/net/i2p/router/transport/TransportUtil.java
index 12bd153d47a18b1d0af46a8061fe681c3abab0da..2eabdeeab1b440b8d62baa16c339be955887a79b 100644
--- a/router/java/src/net/i2p/router/transport/TransportUtil.java
+++ b/router/java/src/net/i2p/router/transport/TransportUtil.java
@@ -120,9 +120,17 @@ public abstract class TransportUtil {
             if (a0 == 169 && a1 == 254) return false;
             // 5/8 allocated to RIPE (30 November 2010)
             //if ((addr[0]&0xFF) == 5) return false;  // Hamachi
+            // Hamachi moved to 25/8 Nov. 2012
+            // Assigned to UK Ministry of Defence
+            // http://blog.logmein.com/products/changes-to-hamachi-on-november-19th
+            if (a0 == 25) return false;
             return true; // or at least possible to be true
         } else if (addr.length == 16) {
             if (allowIPv6) {
+                // loopback, broadcast,
+                // IPv4 compat ::xxxx:xxxx
+                if (addr[0] == 0)
+                    return false;
                 // disallow 2002::/16 (6to4 RFC 3056)
                 if (addr[0] == 0x20 && addr[1] == 0x02)
                     return false;
@@ -133,6 +141,9 @@ public abstract class TransportUtil {
                 // disallow 2001:0::/32 (Teredo RFC 4380)
                 if (addr[0] == 0x20 && addr[1] == 0x01 && addr[2] == 0x00 && addr[3] == 0x00)
                     return false;
+                // Hamachi IPv6
+                if (addr[0] == 0x26 && addr[1] == 0x20 && addr[2] == 0x00 && (addr[3] & 0xff) == 0x9b)
+                    return false;
                 try {
                     InetAddress ia = InetAddress.getByAddress(addr);
                     return