May I suggest a 'divide & conquer' approach.
Eliminate the site in question by trying ftp to ftp.heanet.ie Heanet is a fairly public mirror for linux stuff. another is ftp.esat.net
Install nmap and try nmap -p 21 <some site> That will at least tell you if it's open
Starting Nmap 4.76 (
http://nmap.org ) at 2009-06-18 09:14 IST
Interesting ports on home.no.net (195.159.73.78):
PORT STATE SERVICE
21/tcp open ftp
Nmap done: 1 IP address (1 host up) scanned in 0.34 seconds
If your box doesn't return that, some firewall (Perhaps in your modem or router) is blocking you
Try tftp -v ftp.start.no. It is a verbose mode. I just was told I was connected on port 69 (I presume the connection was made on 21 and sent to 69)