woohoo I found the problem. in the proftpd.conf on the server behind the firewall you need to add something like this to the proftpd.conf file: --- MasqueradeAddress 209.212.xxx.xxx PassivePorts 60000 65535 --- then in the iptables: $IPTABLES -t nat -A PREROUTING -d 209.212.xxx.xxx -p tcp --dport 60000:65535 -j DNAT --to-dest 192.168.0.xxx Now it's working perfectly. Dave