Index: /trunk/src/VBox/NetworkServices/NAT/proxy_dhcp6ds.c
===================================================================
--- /trunk/src/VBox/NetworkServices/NAT/proxy_dhcp6ds.c	(revision 48337)
+++ /trunk/src/VBox/NetworkServices/NAT/proxy_dhcp6ds.c	(revision 48338)
@@ -57,4 +57,8 @@
     pxaddr = netif_ip6_addr(proxy_netif, 0); /* link local */
 
+    /*
+     * XXX: TODO: This is a leftover from testing with IPv6 mapped
+     * loopback with a special IPv6->IPv4 mapping hack in pxudp.c
+     */
     /* advertise ourself as DNS resolver - will be proxied to host */
     pxaddr_nonlocal = NULL;
@@ -117,4 +121,8 @@
     DNSSRV_SET(0, DHCP6_OPTION_DNS_SERVERS);
     DNSSRV_SET(2, 16);          /* one IPv6 address */
+    /*
+     * XXX: TODO: This is a leftover from testing with IPv6 mapped
+     * loopback with a special IPv6->IPv4 mapping hack in pxudp.c
+     */
     memcpy(&dhcp6ds_dns[4], pxaddr_nonlocal, sizeof(ip6_addr_t));
 
Index: /trunk/src/VBox/NetworkServices/NAT/proxy_rtadvd.c
===================================================================
--- /trunk/src/VBox/NetworkServices/NAT/proxy_rtadvd.c	(revision 48337)
+++ /trunk/src/VBox/NetworkServices/NAT/proxy_rtadvd.c	(revision 48338)
@@ -321,8 +321,20 @@
 #endif
     /*
+     * XXX: TODO: Disable "O" flag for now to match disabled stateless
+     * server.  We don't yet get IPv6 nameserver addresses from
+     * HostDnsService, so we have nothing to say, don't tell guests to
+     * come asking.
+     */
+#if 0
+    /*
      * "O" flag.  Tell guests to use DHCP6 for DNS and the like.  This
      * is served by simple stateless server (RFC 3736).
+     *
+     * XXX: "STATEFUL" in the flag name was probably a bug in RFC2461.
+     * It's present in the text, but not in the router configuration
+     * variable name.  It's dropped in the text in RFC4861.
      */
     ra_hdr->flags |= ND6_RA_FLAG_OTHER_STATEFUL_CONFIG;
+#endif
 
     if (is_default) {
Index: /trunk/src/VBox/NetworkServices/NAT/proxytest.c
===================================================================
--- /trunk/src/VBox/NetworkServices/NAT/proxytest.c	(revision 48337)
+++ /trunk/src/VBox/NetworkServices/NAT/proxytest.c	(revision 48338)
@@ -58,5 +58,10 @@
 #endif
 
-#if 1
+    /*
+     * XXX: We use stateless DHCPv6 only to report IPv6 address(es) of
+     * nameserver(s).  Since we don't yet support IPv6 addresses in
+     * HostDnsService, there's no point in running DHCPv6.
+     */
+#if 0
     dhcp6ds_init(proxy_netif);
 #endif