A brief search on google indicates that it's not the application you build, but the protocols installed on BOTH the sender and receiver. With a secure FTP server (FTPS) but an an insecure client (FTP) on the user's system, the user would still be transporting "insecurely" to a secure server.
Maybe sending an encripted document might prove to be an easier implementation.
There's always a better way. The fun is trying to find it!