Bug#422887: Last upgrade of hplip broke the package

[Nicolas DEGAND <nicolas@degand.net>]

Package: hplip
Version: 1.6.10-4
Severity: grave

When upgrading to 1.6.10-4 from 1.6.10-3, the hplip package breaks with
this message :

Paramétrage de hplip (1.6.10-4) ...
Creating/updating hplip user account...
Starting HP Linux Printing and Imaging System: hpiod hpssd failed!
invoke-rc.d: initscript hplip, action "start" failed.
dpkg : erreur de traitement de hplip (--configure) :
 le sous-processus post-installation script a retourné une erreur de
sortie d'état 1
Des erreurs ont été rencontrées pendant l'exécution :
 hplip

If I downgrade, I still encounter this problem. My printer is a HP
Deskjet 5550.

-- System Information:
Debian Release: lenny/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.18-4-amd64 (SMP w/1 CPU core)
Locale: LANG=fr_FR@euro, LC_CTYPE=fr_FR@euro (charmap=ISO-8859-15)
Shell: /bin/sh linked to /bin/bash

Versions of packages hplip depends on:
ii  adduser                       3.102      Add and remove users and groups
ii  coreutils                     5.97-5.3   The GNU core utilities
ii  cupsys                        1.2.7-4    Common UNIX Printing System(tm) - 
ii  hplip-data                    1.6.10-4   HP Linux Printing and Imaging - da
ii  libc6                         2.5-7      GNU C Library: Shared libraries
ii  libcupsys2                    1.2.7-4    Common UNIX Printing System(tm) - 
ii  libgcc1                       1:4.1.2-6  GCC support library
ii  libsnmp10                     5.3.1-5    NET SNMP (Simple Network Managemen
ii  libssl0.9.8                   0.9.8e-4   SSL shared libraries
ii  libstdc++6                    4.1.2-6    The GNU Standard C++ Library v3
ii  libusb-0.1-4                  2:0.1.12-7 userspace USB programming library
ii  lsb-base                      3.1-23.1   Linux Standard Base 3.1 init scrip
ii  python                        2.4.4-3    An interactive high-level object-o
ii  python-qt3                    3.16-1.2   Qt3 bindings for Python
ii  python-support                0.6.3      automated rebuilding support for p

Versions of packages hplip recommends:
ii  cupsys-client            1.2.7-4         Common UNIX Printing System(tm) - 
ii  hpijs                    2.6.10+1.6.10-4 HP Linux Printing and Imaging - gs
ii  hpijs-ppds               2.6.10+1.6.10-4 HP Linux Printing and Imaging - HP
pn  linuxprinting.org-ppds   <none>          (no description available)
pn  python-reportlab         <none>          (no description available)

-- no debconf information