still having ftp issue

Still having a ftp filter problem (unloading ipflt fixes
problem). I am trying to get ftp proxy working.

Per Craig's advise I have only one ftp filter
(ftp-port-pasv-st) from public to public. The proxy appears
to be setup properly as I can log into external proxy sites.
However, I cannot list the contents of the external ftp
site directory. I get disconnected after about 30 seconds.
With ipflt unloaded the connection and listing is almost
instantaneous. Not sure why I can connect but not list the
directory???????????

Any thoughts? Thanks, Chris.