Anyway, i can launch MacPerl with this method too but nothing more. Whatever i add to the command as an argument, MacPerl is launched and that's it, nothing more. So i think the answer to my actual question is just: "No, it's not possible".
In other words the event is a straightforward misc/actv or aevt/odoc event.
If you can arrange for a text file in the same directory as the droplet to list your parameters, then you can manage it.
#ARGS.TXT junk1.txt junk2.txt
#TEST.PL droplet open F, "ARGS.TXT"; $/ = "\015" ; for (<F>) { /^#/ or open F, ">$_" }
When you send the event, junk1.txt and junk2.txt will be created in the same directory as TEST.PL.
JD