Thanks for your reply. We have configured the WS-FTP to connect thru the proxy. It is not connecting in the first place. I think squid does allow uploading of files. Just that we are not able to connect the application thru squid. It does connect thru a nat though, but that will make my life as an admin miserable in having to redefining rules that have already been done in squid. that is why i dont want to have a nat and then put a firewall on it.