The way I did it when I put a password for my list, and I have no idea
if there is any other way, I got the list and in the headers
I put the field pw=_my_selected_password and I put the list back.
From there on Listserv recognized this as the list password.
And of course the headers did not have this field anymore.
The methom I told you earlier is to add a personnal password to the
specific listserv.
 
Spiros