ftp problem

[Imran Imtiaz]

I am running a ftp server on my computer it works fine if i do not enable the firewall but as I enable the firewall on my system ftp doesn't works although I have open port 21 in firewall. my ftp client do gets connected but when i try to dir or any other commands its say no route. below is the output of my ftp client
C:\Documents and Settings\Asif>ftp darkstar.thelakecity.com.pk
Connected to darkstar.thelakecity.com.pk.
220 ProFTPD 1.2.10 Server (ProFTPD Default Installation) [202.59.74.139]
User (darkstar.thelakecity.com.pk:(none)): anonymous
331 Anonymous login ok, send your complete email address as your password.
Password:
230 Anonymous access granted, restrictions apply.
ftp> dir
200 PORT command successful
425 Unable to build data connection: No route to host
ftp> quti
Invalid command.
ftp> quit
221 Goodbye.