package zentyal-core 2.3.21+quantal1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2

[Mino]

This the install output:

Setting up zentyal-core (2.3.21+quantal1) ...
dpkg: error processing zentyal-core (--configure):
 subprocess installed post-installation script returned error exit status 2
E: Sub-process /usr/bin/dpkg returned an error code (1)

ProblemType: Package
DistroRelease: Ubuntu 13.04
Package: zentyal-core 2.3.21+quantal1
ProcVersionSignature: Ubuntu 3.8.0-19.29-generic 3.8.8
Uname: Linux 3.8.0-19-generic x86_64
ApportVersion: 2.9.2-0ubuntu8
Architecture: amd64
Date: Thu May 2 14:30:31 2013
DuplicateSignature:
 Setting up zentyal-core (3.0.19) ...
 dpkg: error processing zentyal-core (--configure):
  subprocess installed post-installation script returned error exit status 2
ErrorMessage: subprocess installed post-installation script returned error exit status 2
InstallationDate: Installed on 2013-05-02 (0 days ago)
InstallationMedia: Ubuntu 13.04 "Raring Ringtail" - Release amd64 (20130424)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: zentyal-core
Title: package zentyal-core 2.3.21+quantal1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 2
UpgradeStatus: No upgrade log present (probably fresh install)

[Launchpad Janitor (janitor)]

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

[clickwir (clickwir)]

Fairly stock install of Ubuntu Server, tried installing Zentyal on it and got this:

sudo apt-get install zentyal-core
Reading package lists... Done
Building dependency tree
Reading state information... Done
The following extra packages will be installed:
  zentyal-common
The following NEW packages will be installed:
  zentyal-common zentyal-core
0 upgraded, 2 newly installed, 0 to remove and 0 not upgraded.
Need to get 584 kB of archives.
After this operation, 3,140 kB of additional disk space will be used.
Do you want to continue [Y/n]?
Get:1 http://us.archive.ubuntu.com/ubuntu/ raring/universe zentyal-common all 2.3.9+quantal1 [29.7 kB]
Get:2 http://us.archive.ubuntu.com/ubuntu/ raring/universe zentyal-core all 2.3.21+quantal1 [555 kB]
Fetched 584 kB in 1s (306 kB/s)
Preconfiguring packages ...
Selecting previously unselected package zentyal-common.
(Reading database ... 98668 files and directories currently installed.)
Unpacking zentyal-common (from .../zentyal-common_2.3.9+quantal1_all.deb) ...
Selecting previously unselected package zentyal-core.
Unpacking zentyal-core (from .../zentyal-core_2.3.21+quantal1_all.deb) ...
Processing triggers for ureadahead ...
Processing triggers for man-db ...
Setting up zentyal-common (2.3.9+quantal1) ...
Setting up zentyal-core (2.3.21+quantal1) ...
dpkg: error processing zentyal-core (--configure):
 subprocess installed post-installation script returned error exit status 2
Processing triggers for ureadahead ...
Errors were encountered while processing:
 zentyal-core
E: Sub-process /usr/bin/dpkg returned an error code (1)