FTP Consistent Failure

From: Mark (me_at_bogus.cc)
Date: 03/02/04 

Date: 2 Mar 2004 15:16:11 -0800

Help,
  I can't figure out what I'm doing wrong here. I've installed SBS2003
comfortably and I'm trying to get an FTP server running on it. I
understand the security issues involved but...

  Anyway, I'm running a stock SBS premium server with ISA firewall. I
have two FTP sites on it that run. For both sites I can transfer a few
files to the remote location and then the transfer grinds to a halt.

  Here's a typical piece of the log from AceFTP

TYPE A
200 Type set to A.
PORT 172,16,3,10,15,159
200 PORT command successful.
LIST
150 Opening ASCII mode data connection for /bin/ls.
226 Transfer complete.
Transferred 5,889 bytes in 0.07 seconds (82.16 KB/s)
Queue completed in 0.41 seconds
PORT 172,16,3,10,15,160
200 PORT command successful.
RETR ref_Joint & Muscle.htm
150 Opening ASCII mode data connection for ref_Joint & Muscle.htm(3841
bytes).
226 Transfer complete.
Transferred 3,841 bytes in 0.01 seconds (375.10 KB/s)
<<... a bunch of successful port and retr commands follow... then..>>
PORT 172,16,3,10,15,172
200 PORT command successful.
RETR Store Ailments.htm
500 'TR Store Ailments.htm': command not understood
Unable to open data socket
Failed [Unable to open data socket]
PORT 172,16,3,10,15,173
500 '': command not understood
Unable to open data socket
Delaying for 5 seconds before next attempt...
Processing item, attempt 2...
PORT 172,16,3,10,15,174
500 'RT 65,81,160,183,15,174': command not understood
Unable to open data socket
Delaying for 5 seconds before next attempt...
Aborting queue processing...
Aborting queue processing...
Failed [Unable to open data socket]
Queue processing aborted.

Does anyone have aay idea of what's going on here? I seem to be losing
parts of a packet.

M