inet & leased line

Is there any nown problems with the inet controll and a leased line, have a 128k leased line which allows me to surf no problem but inet controll does not work properly comes back with ftp error '425 cannot open data connection' yet works fine with a modem? im not running a proxy so surely it should just be a direct connection? any help gratefully apreciated!

I have a similar problem with api calls I'm using with ftp files. Did you find a solution???