I sometimes use the command-line FTP program that's included with Mac OS X to upload files to my ISP. Since Tiger was released, I have had problems. The login process always works fine, but when I try to do a dir command, for example, the program stalls and I never get the results.
For a while I suspected my Linksys router to be the problem. But I tried the same FTP commands on a Linux box I have, and everything worked fine. So it really is a Tiger issue.
After some investigation, I found that Tiger's FTP program has an option set by default: EPSV/EPRT on IPv4. To disable this, you must issue the epsv4 command in the FTP program before doing anything else. From now on, any command will work correctly and as expected.
[kirkmc adds: The man page for the ftp command mentions this option and command. It seems that the option exists in Panther, but was not enabled by default.]
Mac OS X Hints
http://hints.macworld.com/article.php?story=2006042216241566