Monitor IFS in real time for FTP put (new files received)

We need to monitor the IFS in real time for new files received via the FTP
'put' command. We have an application where a vendor's machine is going to
FTP us a file when a group of orders is deposited at a wrapping station. We
need to gather that information immediately and print invoices at that
wrapping station. Here is what the vendor has stated as givens:
1. They will only FTP the file to the IFS.
2. They will NOT send a line to submit an iSeries command as part of the FTP
put.

We have looked at MONIFS command in IFSTOOL on www.easy400.net but looking
deeper in the code, it monitors the journal once a minute. If I change this
to look through every second, isn't this going to kill system performance.

Another option we may try is BVStool's FTPTOOL. The documentation makes it
look promising based on this sentence: 'Add "triggers" that will run any
command or program when certain FTP commands are used'

Any other ideas?

Thanks in advance.

Blair Hamren