Tell the kernel to route traffic to 127.0.0.0/8:
root@george:~# sysctl -w net.ipv4.conf.docker0.route_localnet=1
(You might need to do this for additional interfaces -- works for me)
Make sure your INPUT chain of the filter table will accept the connection:
root@george:~# iptables -I INPUT -i docker+ -d 127.0.0.0/8 -j ACCEPT