package slapd 2.4.25-1.1ubuntu4.1 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 1

[Anthony Watts]

this issue started in an upgrade from 10.04 LTS to 1.10. it was evident again in the 10.10 -> 11.04 upgrade (report in an earlier bug track) and continued inot the upgrade from 11.04 to 11.10

ProblemType: Package
DistroRelease: Ubuntu 11.10
Package: slapd 2.4.25-1.1ubuntu4.1
ProcVersionSignature: Ubuntu 2.6.38-13.52-generic 2.6.38.8
Uname: Linux 2.6.38-13-generic x86_64
NonfreeKernelModules: nvidia
ApportVersion: 1.23-0ubuntu4
Architecture: amd64
CNConfig: Error: command ['/usr/bin/ldapsearch', '-Q', '-LLL', '-Y EXTERNAL', '-H ldapi:///', '-b cn=config'] failed with exit code 255: ldap_sasl_interactive_bind_s: Can't contact LDAP server (-1)
Date: Wed Dec 14 07:51:00 2011
ErrorMessage: ErrorMessage: subprocess installed post-installation script returned error exit status 1
SourcePackage: openldap
SysLog:

Title: package slapd 2.4.25-1.1ubuntu4.1 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 1
UpgradeStatus: Upgraded to oneiric on 2011-12-13 (0 days ago)