[gftp] gftp won't connect with cox.net

[bbales <bbales@xxxxxxx>]

I have been using gftp with linux RedHat 9 for several years and have 
several web pages on members.cox.net, which I maintain with gftp.  
Suddenly a couple of weeks ago, I was unable to connect in order to update 
my sites.  I get the following messages and the right window stays empty:

Looking up members.cox.net
Trying members.cox.net:21
Connected to members.cox.net:21
220 ProFTPD 1.2.8 Server (Personal Web Pages) [68.1.17.8]
USER bartonm 
331 Password required for bartonm.
PASS xxxx
230 User bartonm logged in.
TYPE I 
200 Type set to I
PWD 
257 "/" is current directory.
PASV 
227 Entering Passive Mode (68,1,17,8,28,124).
Cannot create a data connection: No route to host
Disconnecting from site members.cox.net

Using gftp-2.0.14.  I tried gftp-2.0.18 on a kubuntu machine, went around 
my firewall, tried all the different users and passwords.  I can ping 
68.1.17.8.

My browsers all can access the internet and my web pages.  I contacted cox 
and they showed me a mickey-mouse way to upload pages and it worked, 
although I wouldn't want to depend on doing it that way.

Seems obvious that there is nothing wrong with  gftp, but I'm stumped.

What is passive mode?

Any help would be appreciated,
bruce