Installing BitDefender Security for Mail Servers on Ubuntu 7.10 or newer Ubuntu 7.10 (code name "Gutsy Gibbon") is the first Debian-based distribution to use a modified version of the package management tool dpkg, which queues all ldconfig calls to be ran after installing a batch of packages. In the previous versions, all ldconfig calls were ran immediately. BitDefender packages run ldconfig during the configuration stage and rely on its immediate effects.
Therefore, starting with Ubuntu 7.10, trying to set up BitDefender Security for Mail Servers or BitDefender Security for Samba version 2.1-x (and earlier) will result in an install problem, because the 2.1-x (and earlier) version doesn't "know" about the new trigger mechanism used by Ubuntu's dpkg.
Debian GNU/Linux 3.1 has a bug in Webmin 1.180-3 which prevents work with 3rd party modules. Thus it is impossible to use the Webmin module included in the BitDefender packages.