package openswan 1:2.6.38-1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 128

While installing L2TP IPsec VPN Applet I got this error

ProblemType: Package
DistroRelease: Ubuntu 14.04
Package: openswan 1:2.6.38-1
ProcVersionSignature: Ubuntu 3.13.0-44.73-generic 3.13.11-ckt12
Uname: Linux 3.13.0-44-generic x86_64
ApportVersion: 2.14.1-0ubuntu3.6
Architecture: amd64
Date: Tue Feb 3 12:50:20 2015
DuplicateSignature: package:openswan:1:2.6.38-1:subprocess installed post-installation script returned error exit status 128
ErrorMessage: subprocess installed post-installation script returned error exit status 128
InstallationDate: Installed on 2014-06-12 (236 days ago)
InstallationMedia: Ubuntu 14.04 LTS "Trusty Tahr" - Release amd64 (20140417)
SourcePackage: openswan
Title: package openswan 1:2.6.38-1 failed to install/upgrade: subprocess installed post-installation script returned error exit status 128
UpgradeStatus: No upgrade log present (probably fresh install)