How do I monitor what commands my ftp application is sending to a ftp server

You can use the Wireshark application: http://www.wireshark.org/ It should have decent parsing capabilities for FTP as well as other protocols.

Can you configure a proxy with the client? Then you could install an ftp proxy server using the logging on that to see what's going on? There's a proxy server for Linux here: http://frox.sourceforge.net/doc/FAQ.html Paul.

Do you have access to ftp-server logs? Its likely those commands would be logged there. If they aren't, your next option would be to configure the server to log them, if you have access. If thats not an option or server does not log such things, then you have to go to either packet sniffer or a proxy, as suggested by previous posters.

On Unix, tcpdump might be your friend. Maybe you should first state which OS you're targeting, though.

If you have the ability (often requiring root access) to use a packet sniffer, http://www.circlemud.org/~jelson/software/tcpflow/ sniffing the TCP control channel will show you the commands and responses going back and forth in an easy-to-read format. If you don't have such access, tools such as ktrace and strace will allow you to see all data read and written on the socket for this connection, though it will be a little work to extract it. If you could tell us just what tool you were using for HTTP traffic, that would allow us to look for something similar for FTP traffic.