incorrect NXDOMAIN response from DNS server

  do you know:
  - name of particular implementation which have/had this bug?

"BBC Intelligent Load Balancing DNS Server"

  i heard that it was based on lbnamed 1.2. i have confirmed that
  lbnamed 1.2 distribution contains buggy sample config file
  (perl5/lbnamed.conf{,.example} in the distribution).
  if any of you are running load balancing nameserver based on lbnamed
  1.2, please fix it. thanks!