package otrs2 3.2.9-2 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 1

During upgrade from 13.04 to 13.10 the OTRS upgrade fails during the database upgrade.

An error occurred while upgrading the database:

/usr/share/dbconfig-common/scripts/otrs2/upgrade/mysql/3.2.0 exited with non-zero status

Fortunately, /var/cache/dbconfig-common/backups/otrs2_3.1.7+dfsg1-8.mysql holds a backup of the database, made just before the upgrade.

If at this point you choose "retry", you will be prompted with all the configuration questions once more and another attempt will be made at performing the operation. "retry (skip questions)" will immediately attempt the operation again, skipping all questions. If you choose "abort", the operation will fail and you will need to downgrade, reinstall, reconfigure this package, or otherwise manually intervene to continue using it.

ProblemType: Package
DistroRelease: Ubuntu 13.10
Package: otrs2 3.2.9-2
ProcVersionSignature: Ubuntu 3.8.0-34.49-generic 3.8.13.12
Uname: Linux 3.8.0-34-generic x86_64
ApportVersion: 2.12.5-0ubuntu2.2
Architecture: amd64
Date: Fri Jan 31 08:48:33 2014
DuplicateSignature: package:otrs2:3.2.9-2:ErrorMessage: subprocess installed post-installation script returned error exit status 1
ErrorMessage: ErrorMessage: subprocess installed post-installation script returned error exit status 1
InstallationDate: Installed on 2012-10-30 (457 days ago)
InstallationMedia: Ubuntu-Server 12.04 LTS "Precise Pangolin" - Release amd64 (20120424.1)
MarkForUpload: True
PackageArchitecture: all
SourcePackage: otrs2
Title: package otrs2 3.2.9-2 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to saucy on 2014-01-31 (0 days ago)