gFTP problem

[nhtrader]

kubuntu 10.04.3 LTS
gFTP 2.0.19
FileZilla 3.5.0


PROBLEM: I'm trying to access my home FTP server and I'm getting an error message after a success login:
"cannot create a data connection: No Route to host"


STATUS:
1. I'm using a kubuntu PC with gFTP (client:kub1) to access another kubuntu PC (server:kub2).

2. gFTP on kub1 works with all other ftp sites except home FTP server.

3. From same remote location a windows based PC using FileZilla FTP client can access home FTP server and transfers work ok (upload and download-ok).

4. I've read gFTP FAQs regarding this problem and gFTP still doesn't work.

The recommended change was to disable "Passive File Transfers". When I make this change the error message changes to:
"500 Illegal Port Command Invalid Response '5' received from server"

Support Files that were checked:

1. /etc/hosts
1. /etc/hosts.deny
2. /etc/hosts.allow
3. /etc/resolv.conf

no offending commands were discovered.


So I have a working FTP client and a working FTP server but I can't get them to work together

Please advise