+## Set up NAT protocol helpers. In particular, SIP needs some special
+## twiddling.
+run modprobe nf_conntrack_sip \
+ ports=5060 \
+ sip_direct_signalling=0 \
+ sip_direct_media=0
+for p in ftp sip h323; do
+ run modprobe nf_nat_$p
+done
+
+## Forbid anything complicated to the NAT address.
+run iptables -A INPUT -d 62.49.204.158 ! -p icmp -j REJECT
+