When you are typing "PASSIVE" in your command-line client, you are probably turning passive ON, not OFF. Passive generally works with firewalls. So try your code with Passive => 1.

Besides that, there is an easier way. There is already code in Net::FTP to handle proxies. You need to add some code to your libnet.cfg file (typically in the Net/ directory, but there are ways of making user-local copies). See perldoc Net::Config. My Net/libnet.cfg looks like this:

{
  ftp_firewall => 'corpgate03',
  ftp_firewall_type => 1,
  ftp_ext_passive => 1,
  local_netmask => [
    "162.134.0.0/16", "172.24.0.0/16", "192.168.0.0/16",
  ],
}
[download]