FTP active mode doesn't work properly with PF and ftp-proxy

["Marcos Biscaysaqu - ThePacific.net" <marcos_(_at_)_ThePacific_(_dot_)_Net>]

Hi there.
Im running a pf firewall doing NAT, so as all the manuals said I setup 
the ftp-proxy to allow ftp clients behind the PF NAT to connect to 
external FTPs server,  but the way this work all the data traffic coming 
back when I running an ftp connection on active mode, it is coming back 
with the IP number of my  bsd box, some windows client doesn't care 
about it, but Mac os users or NCFTP drop the connections when this is 
happening.
I tried all the possibles options on ftp-proxy and all the version 
possibles with the same end.

somebody know how fix this, or if it another option to make work ftp 
clients on Active mode with PF?

thanks
Marcos Biscaysaqu
Thepacific.net