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

[GrahamT]

updating from 10.04 to 12.04

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: samba4 4.0.0~alpha18.dfsg1-4ubuntu2
ProcVersionSignature: Ubuntu 2.6.32-36.79-generic-pae 2.6.32.46+drm33.20
Uname: Linux 2.6.32-36-generic-pae i686
ApportVersion: 2.0.1-0ubuntu7
Architecture: i386
Date: Sun Apr 29 12:39:03 2012
EcryptfsInUse: Yes
ErrorMessage: ErrorMessage: subprocess installed post-installation script returned error exit status 126
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Release Candidate i386 (20100419.1)
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 2012-04-29 (0 days ago)