I have a Nokia M1112 with NAPT configuration. I have opened the ports 21 (FTP), 25 (SMTP) and 110 (POP3), so when you connect to the public IPs you are really connecting to one machine within my LAN. . The ports 25 and 110 work properly but port 21 (FTP) does not, because you need to connect in PASV (passive mode) in FTP service if you want to get the list of files, and Microsoft's FTP program does not support this feature. I know I could use another FTP program but we need to use Microsoft for another reasons. How can I solve this? I have not found how to configure my Nokia to allow connections without PASV mode.
Can anybody help me?

Gracias from Spain.