Setting up an FTP server under RedHat 9.0

I know this exposes me as a Linux newbie but... I've just setup my first FTP server on RedHat. And found a couple interesting things. It was part of my lab assignment today (at school). After getting the vsftpd daemon loaded and running I started trying to "put" and "get" files from the server.

Interestingly when using the "put" command I had to rename the file otherwise it returned an error saying "could not create file". The instructor thought this weird and hadn't seen it function that way before. So in order to upload the file "firefox-1.0-installer.tar.gz" I had to use the command "put /home/user/firefox-1.0-installer.tar.gz Firefox" which would then upload the file renaming it as "Firefox". Any explanations? It worked like that for the other guys too. We expected to be able to upload it preserving the local name.