package slapd 2.4.28-1.1ubuntu4 failed to install/upgrade: ErrorMessage: subprocess installed post-installation script returned error exit status 1

Got up slapd running with this trick http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=593550#10
But still the configure-part seems to fail:

# ps aux
openldap 2456 3.1 0.8 840172 17560 ? SLsl 13:32 0:08 /usr/sbin/slapd [...]
# apt-get upgrade
Reading package lists... Done
Building dependency tree
Reading state information... Done
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.
1 not fully installed or removed.
After this operation, 0 B of additional disk space will be used.
Do you want to continue [Y/n]?
Setting up slapd (2.4.28-1.1ubuntu4) ...
  Backing up /etc/ldap/slapd.d in /var/backups/slapd-2.4.25-1.1ubuntu4... done.
  Moving old database directories to /var/backups:
  Loading from /var/backups/slapd-2.4.25-1.1ubuntu4:
  - directory dc=ba5,dc=sim,dc=no... failed.

Loading the database from the LDIF dump failed with the following
error while running slapadd:
    /var/backups/slapd-2.4.25-1.1ubuntu4/dc=ba5,dc=sim,dc=no.ldif: No such file or directory
dpkg: error processing slapd (--configure):
 subprocess installed post-installation script returned error exit status 1
Errors were encountered while processing:
 slapd
E: Sub-process /usr/bin/dpkg returned an error code (1)

Hi Christian

Thanks for taking the time to report this bug in Ubuntu.

It looks like something might have been wrong with your ldap configuration pre-upgrade.

Please can you run the following commands:

 sudo slaptest -F /var/backups/slapd-2.4.25-1.1ubuntu4

and attach the output to this bug report. Hopefully this might give us some pointers as to where the issue lies.

Marking 'Incomplete' pending your response. Please set back to 'New' once you have provided the requested information.

Thanks