200 PORT command successful. Consider using PASV. Hungs.

[Avi Ma'ayan]

Hi,
 
I am trying to tranfer a file from my desktop to a RedHat server using FTP. It used to work yesterday but today it just hungs after ftp>put file with this message: "200 PORT command successful. Consider using PASV." The file is create at the server but it is empty. I can do other ftp command such as "cd" which work fine. Any ideas? What might have broken, I haven't changed any setting? Could it be something with the network?
 
Thanks for your help.
 
avi maayan