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

[Caron Wills]

We also need info:

1.
lsb_release -rd
Description: Ubuntu 12.04 LTS
Release: 12.04

2.
apt-cache policy samba4
samba4:
  Installed: 4.0.0~alpha18.dfsg1-4ubuntu2
  Candidate: 4.0.0~alpha18.dfsg1-4ubuntu2
  Version table:
 *** 4.0.0~alpha18.dfsg1-4ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
        100 /var/lib/dpkg/status

apt-cache policy winbind4
winbind4:
  Installed: 4.0.0~alpha18.dfsg1-4ubuntu2
  Candidate: 4.0.0~alpha18.dfsg1-4ubuntu2
  Version table:
 *** 4.0.0~alpha18.dfsg1-4ubuntu2 0
        500 http://us.archive.ubuntu.com/ubuntu/ precise/universe amd64 Packages
        100 /var/lib/dpkg/status

3.
I expected "sudo apt-get install winbind4" to complete without any exceptions ("sudo apt-get install winbind" works).

4.
instead, there were errors processing samba4 due to an invalid smb.conf file. It looks like there were several unknown parameters in that file.

ProblemType: Package
DistroRelease: Ubuntu 12.04
Package: samba4 4.0.0~alpha18.dfsg1-4ubuntu2
ProcVersionSignature: Ubuntu 3.2.0-24.39-generic 3.2.16
Uname: Linux 3.2.0-24-generic x86_64
NonfreeKernelModules: fglrx
ApportVersion: 2.0.1-0ubuntu7
Architecture: amd64
Date: Thu May 24 12:44:30 2012
ErrorMessage: subprocess installed post-installation script returned error exit status 126
InstallationMedia: Ubuntu 12.04 LTS "Precise Pangolin" - Beta amd64 (20120328)
SourcePackage: samba4
Title: package samba4 4.0.0~alpha18.dfsg1-4ubuntu2 failed to install/upgrade: subprocess installed post-installation script returned error exit status 126
UpgradeStatus: No upgrade log present (probably fresh install)