package otrs2 (not installed) failed to install/upgrade: subprocess new pre-installation script returned error exit status 1

Binary package hint: otrs2

Warning: The home dir /usr/share/otrs you specified can't be accessed: No such file or directory
adduser: The user `otrs' already exists. Exiting.
dpkg: error processing /var/cache/apt/archives/otrs2_2.4.9+dfsg1-3_all.deb (--unpack):
 subprocess new pre-installation script returned error exit status 1
Selecting previously deselected package procmail.
Unpacking procmail (from .../procmail_3.22-19_amd64.deb) ...
Selecting previously deselected package postfix.
Unpacking postfix (from .../postfix_2.8.2-1ubuntu2.1_amd64.deb) ...
Processing triggers for man-db ...
Processing triggers for doc-base ...
Processing 1 added doc-base file(s)...
Registering documents with scrollkeeper...
Processing triggers for ufw ...
Processing triggers for ureadahead ...
ureadahead will be reprofiled on next reboot
Errors were encountered while processing:
 /var/cache/apt/archives/otrs2_2.4.9+dfsg1-3_all.deb
E: Sub-process /usr/bin/dpkg returned an error code (1)

ProblemType: Package
DistroRelease: Ubuntu 11.04
Package: otrs2 (not installed)
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic x86_64
Architecture: amd64
Date: Tue May 24 19:19:59 2011
ErrorMessage: subprocess new pre-installation script returned error exit status 1
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release amd64 (20100429)
SourcePackage: otrs2
Title: package otrs2 (not installed) failed to install/upgrade: subprocess new pre-installation script returned error exit status 1
UpgradeStatus: Upgraded to natty on 2011-04-30 (24 days ago)