The following reply was made to PR pkg/47054; it has been noted by GNATS.
From: Robert Elz<kre%munnari.OZ.AU@localhost>
Looks suspiciously like NAT death& EPSV - an FTP server& client that
understand (and use) EPSV (or EPRT) separated by a NAT that has no
idea what those are about (though as it is now close to 15 years since
they were added, such a thing is really inexcusable - but they certainly
exist).
You could try disabling EPSV in the client, and see if that helps.
Otherwise, try a tcpdump of the connection, and see what is really
happening.