Error in function: SystemError: E:Sub-process /usr/bin/dpkg returned an error code (1)

[Daniel Manova]

Errors were encountered while processing:
 qmail
 qmail-run
Error in function:
SystemError: E:Sub-process /usr/bin/dpkg returned an error code (1)
Setting up qmail (1.06-4) ...

The hostname -f command returned: $1

Your system needs to have a fully qualified domain name (fqdn) in
order to install the var-qmail packages.

Installation aborted.

dpkg: error processing qmail (--configure):
 subprocess installed post-installation script returned error exit status 1
dpkg: dependency problems prevent configuration of qmail-run:
 qmail-run depends on qmail (>= 1.06-2.1); however:
  Package qmail is not configured yet.
dpkg: error processing qmail-run (--configure):
 dependency problems - leaving unconfigured

ProblemType: Bug
DistroRelease: Ubuntu 12.04
Package: qmail 1.06-4
ProcVersionSignature: Ubuntu 3.2.0-37.58-generic-pae 3.2.35
Uname: Linux 3.2.0-37-generic-pae i686
ApportVersion: 2.0.1-0ubuntu17.1
Architecture: i386
Date: Fri Feb 1 22:03:23 2013
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Release i386 (20120423)
MarkForUpload: True
SourcePackage: netqmail
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.