How to know when upload has finished

[lars.bruun-hansen]

using the ftp server as a standalone server.

How do I know when a file upload has finished? 

Compare to proftpd which uploades into .in.filename and only when the
upload has completed the file is renamed to its correct name.

I wouldn't like to have to write a Java hook to know this, i.e. I would
very much like to continue using the server as an uncomplicated, easy to
install, low requirements, fast, plain-vanilla standalone ftp server.

Is the above feature already available via some parameter that I've
missed? If not this would be my wish for a new feature.

Lars