Regrettably I have a third party application that uses FTP on non standard ports.
With IPF it was possible to proxy FTP on other ports than 21 like this: map ppp0 192.168.9.0/24 -> 0/32 proxy port 42 ftp/tcp map ppp0 192.168.9.0/24 -> 0/32 proxy port 63 ftp/tcp Is something similar possible with PF on OpenBSD 3.1? Daniel Polak
