[Mailman-Users] variable %(addr) not interpreted in customized template

[Katharina]

I have tried to cusotmize the welcome message in the usual way: created
a directory lists/<mylist>/en and copied templates/subscribeack.txt to
this directory where I edited it. In the new template I wanted as well
to make the address of the welcomed member visible and so I used the
variable %(addr). This has unfortunatelly not worked: What I got back
was the string "%(addr)" itself and no email address. What should I do
to get it write?
 
Thanks!