ok, so the word on the street is that you need probably inception to do this.

install inception, {look up how to do this, theres plenty of resources available}, and then run the lock script with ariadne like this:
ariadne perl /home/user/MyDocs/lock.pl

if that works, you can stick that in your n9bm config file.

if that doesnt work, try poking around the inception thread and asking how to lock/unlock with a command as user in closed mode.