mailman_transport:
   driver = pipe
   command = MM_WRAP \
          '${if def:local_part_suffix \
                {${sg{$local_part_suffix}{-(\\w+)(\\+.*)?}{\$1}}} \
                {post}}' \
          $local_part
   current_directory = MM_HOME
   home_directory = MM_HOME
   user = MM_UID
   group = MM_GID