package samba4 4.0.0~alpha18.dfsg1-4ubuntu2 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 126

[Colin Smart]

Description: Ubuntu 12.04 LTS
Release: 12.04

samba:
  Installed: 2:3.6.3-2ubuntu2.1
  Candidate: 2:3.6.3-2ubuntu2.1
  Version table:
 *** 2:3.6.3-2ubuntu2.1 0
        500 http://gb.archive.ubuntu.com/ubuntu/ precise-updates/main i386 Packages
        500 http://security.ubuntu.com/ubuntu/ precise-security/main i386 Packages
        100 /var/lib/dpkg/status
     2:3.6.3-2ubuntu2 0
        500 http://gb.archive.ubuntu.com/ubuntu/ precise/main i386 Packages

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: samba4
ProcVersionSignature: Ubuntu 3.2.0-24.37-generic 3.2.14
Uname: Linux 3.2.0-24-generic i686
ApportVersion: 2.0.1-0ubuntu7
Architecture: i386
Date: Sat May 5 02:17:12 2012
ErrorMessage: ErrorMessage: subprocess installed post-installation script returned error exit status 126
InstallationMedia: Ubuntu 11.10 "Oneiric Ocelot" - Release i386 (20111012)
SourcePackage: samba4
Title: package samba4 4.0.0~alpha18.dfsg1-4ubuntu2 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 126
UpgradeStatus: Upgraded to precise on 2012-05-06 (0 days ago)