ftp problem

[#1]

I am having difficulty connecting to ftp servers from my Plusnet broadband connection.
I have a Voyager 210 router with IP Filtering disabled.
According to MyAccount on plusnet my broadband firewall is turned off.
If I attempt to ftp to , say, ftp.kernel.org , I'm not seeing any response from the other end.
This happens using command-line ftp and WinSCP on Windows XP, and the Solaris ftp client.
ZoneAlarm is set to allow the connection on XP, and there is no firewall running on the Solaris system.
When I run
# ftp ftp.kernel.org
Solaris snoop reports:
# snoop | grep kernel
Using device e1000g0 (promiscuous mode)
    myhost -> pub1.kernel.org FTP C port=36069
    myhost -> pub1.kernel.org FTP C port=36069
    myhost -> pub1.kernel.org FTP C port=36069
with apparently nothing coming back.
Any suggestions as to what might be causing this? ftp.kernel.org is definitely up, I can ftp to it from another service provider connection.

[#2]

Have you exceeded any peak time allowance limits - some packages block FTP when you do?
It works fine for me so must still be something your end. The fact that all systems have a problem points to the router. Have you tried resetting it back to factory defaults and configuring it again - for outgoing initiated FTP you should not need to set-up any firewall rules.

[#3]

Peter has hit the nail on the head I think, looking at your account you've reached the usage allowance on your account. Have a look at the table here to see how it affects you.
Looks like your billing date is coming up so this will reset at that point.

[#4]

That'll be it then! Thanks for the responses. I knew the speed would be affected but I didn't realise that some protocols got blocked altogether.
Must have a quiet word with the kids to see where all the bandwidth is going!