Black texts and pictures are bold and blurred on color prints with CP1025

EDIT : the same problem is reported here : https://answers.launchpad.net/hplip/+question/176428
Sorry for the duplicate question

When I print documents with my new CP1025 in color mode, black areas on the sheets (in particular characters and vectorial graphics) are printed with some kind of blur or shadow around it. Colored areas (eg. colored characters, pictures...) are correctly printed.

It seems to occur whatever the document I print (pdf, odt, jpg ...), and often make it unreadable in particular for small fonts. However, it doesn't affect black & white prints, on which everything is sharp (text, photos...)

Could it be a color profile issue ? Thank you in advance for your help.

My OS : Ubuntu 11.10
Here is the result of "hp-check -t" :

hp-check[3681]: info: :
Initializing. Please wait...
Ubuntu

11.10

scheduler is running

Linux lf123a 2.6.38-11-generic-phc #48~phc0-Ubuntu SMP Tue Aug 23 03:01:37 UTC 2011 i686 i686 i386 GNU/Linux

hp-check[3681]: info: :
hp-check[3681]: info: :---------------
hp-check[3681]: info: :| SYSTEM INFO |
hp-check[3681]: info: :---------------
hp-check[3681]: info: :
hp-check[3681]: info: :Basic system information:
hp-check[3681]: info: :Linux lf123a 2.6.38-11-generic-phc #48~phc0-Ubuntu SMP Tue Aug 23 03:01:37 UTC 2011 i686 i686 i386 GNU/Linux

hp-check[3681]: info: :
hp-check[3681]: info: :Distribution:
hp-check[3681]: info: :ubuntu 11.10
hp-check[3681]: info: :
hp-check[3681]: info: :Checking Python version...
hp-check[3681]: info: :OK, version 2.7.2 installed
hp-check[3681]: info: :
hp-check[3681]: info: :Checking PyQt 4.x version...
hp-check[3681]: info: :OK, version 4.8.5 installed.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for CUPS...
hp-check[3681]: info: :Status: scheduler is running
warning: Version: (cups-config) Not available. Unable to determine installed version of CUPS.)
warning: /etc/cups/cupsd.conf file not found or not accessible.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dbus/python-dbus...
hp-check[3681]: info: :dbus daemon is running.
hp-check[3681]: info: :python-dbus version: 0.84.0
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :------------------------------------
hp-check[3681]: info: :| COMPILE AND RUNTIME DEPENDENCIES |
hp-check[3681]: info: :------------------------------------
hp-check[3681]: info: :
note: To check for compile-time only dependencies, re-run hp-check with the -c parameter (ie, hp-check -c).
note: To check for run-time only dependencies, re-run hp-check with the -r parameter (ie, hp-check -r).
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: CUPS - Common Unix Printing System...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: CUPS DDK - CUPS driver development kit...
warning: NOT FOUND! This is an OPTIONAL/RUNTIME ONLY dependency. Some HPLIP functionality may not function properly.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: CUPS devel- Common Unix Printing System development files...
error: NOT FOUND! This is a REQUIRED/COMPILE TIME ONLY dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: CUPS image - CUPS image development files...
error: NOT FOUND! This is a REQUIRED/COMPILE TIME ONLY dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: DBus - Message bus system...
error: NOT FOUND! This is a REQUIRED dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: gcc - GNU Project C and C++ Compiler...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: GhostScript - PostScript and PDF language interpreter and previewer...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libcrypto - OpenSSL cryptographic library...
error: NOT FOUND! This is a REQUIRED dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libjpeg - JPEG library...
error: NOT FOUND! This is a REQUIRED dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libnetsnmp-devel - SNMP networking library development files...
error: NOT FOUND! This is a REQUIRED dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libpthread - POSIX threads library...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libtool - Library building support services...
error: NOT FOUND! This is a REQUIRED/COMPILE TIME ONLY dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: libusb - USB library...
error: NOT FOUND! This is a REQUIRED dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: make - GNU make utility to maintain groups of programs...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: PIL - Python Imaging Library (required for commandline scanning with hp-scan)...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: PolicyKit - Administrative policy framework...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: PyQt 4 DBus - DBus Support for PyQt4...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python DBus - Python bindings for DBus...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python devel - Python development files...
error: NOT FOUND! This is a REQUIRED/COMPILE TIME ONLY dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python libnotify - Python bindings for the libnotify Desktop notifications...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python XML libraries...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python 2.3 or greater - Required for fax functionality...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Python 2.2 or greater - Python programming language...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: Reportlab - PDF library for Python...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: SANE - Scanning library...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: SANE - Scanning library development files...
error: NOT FOUND! This is a REQUIRED/COMPILE TIME ONLY dependency. Please make sure that this dependency is installed before installing or running HPLIP.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: scanimage - Shell scanning program...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for dependency: xsane - Graphical scanner frontend for SANE...
warning: NOT FOUND! This is an OPTIONAL/RUNTIME ONLY dependency. Some HPLIP functionality may not function properly.
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :----------------------
hp-check[3681]: info: :| HPLIP INSTALLATION |
hp-check[3681]: info: :----------------------
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :Currently installed HPLIP version...
hp-check[3681]: info: :HPLIP 3.11.7 currently installed in '/usr/share/hplip'.
hp-check[3681]: info: :
hp-check[3681]: info: :Current contents of '/etc/hp/hplip.conf' file:
hp-check[3681]: info: :# hplip.conf. Generated from hplip.conf.in by configure.

[hplip]
version=3.11.7

[dirs]
home=/usr/share/hplip
run=/var/run
ppd=/usr/share/ppd/hplip/HP
ppdbase=/usr/share/ppd/hplip
doc=/usr/share/doc/hplip-doc/HTML
icon=no
cupsbackend=/usr/lib/cups/backend
cupsfilter=/usr/lib/cups/filter
drv=/usr/share/cups/drv

# Following values are determined at configure time and cannot be changed.
[configure]
network-build=yes
pp-build=yes
gui-build=yes
scanner-build=yes
fax-build=yes
dbus-build=yes
cups11-build=no
doc-build=yes
shadow-build=no
hpijs-install=yes
foomatic-drv-install=yes
foomatic-ppd-install=yes
foomatic-rip-hplip-install=no
hpcups-install=yes
cups-drv-install=yes
cups-ppd-install=no
internal-tag=3.11.7
restricted-build=no
ui-toolkit=qt4
qt3=no
qt4=yes
policy-kit=yes
hpijs-only-build=no
lite-build=no
udev-acl-rules=yes
hpcups-only-build=no
hpijs-only-build=no

hp-check[3681]: info: :
hp-check[3681]: info: :Current contents of '/var/lib/hp/hplip.state' file:
hp-check[3681]: info: :[plugin]
installed = 1
eula = 1

hp-check[3681]: info: :
hp-check[3681]: info: :Current contents of '~/.hplip/hplip.conf' file:
hp-check[3681]: info: :[settings]
systray_visible = 0
systray_messages = 0

[last_used]
device_uri = "hp:/usb/HP_LaserJet_CP1025?serial=00000GF02F0ES"
printer_name =
working_dir = .

[commands]
scan = /usr/bin/simple-scan %SANE_URI%

[refresh]
rate = 30
enable = false
type = 1

[polling]
enable = false
interval = 5
device_list =

[fax]
voice_phone =
email_address =

[installation]
date_time = 01/12/2011 20:30:29
version = 3.11.7

hp-check[3681]: info: :
hp-check[3681]: info: :--------------------------
hp-check[3681]: info: :| DISCOVERED USB DEVICES |
hp-check[3681]: info: :--------------------------
hp-check[3681]: info: :
hp-check[3681]: info: : Device URI Model
hp-check[3681]: info: : ----------------------------------------------- -----------------------------------------------
hp-check[3681]: info: : hp:/usb/HP_LaserJet_CP1025?serial=00000GF02F0ES HP LaserJet CP1025
hp-check[3681]: info: :
hp-check[3681]: info: :---------------------------------
hp-check[3681]: info: :| INSTALLED CUPS PRINTER QUEUES |
hp-check[3681]: info: :---------------------------------
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :HP_LaserJet_CP1025
hp-check[3681]: info: :------------------
hp-check[3681]: info: :Type: Printer
hp-check[3681]: info: :Device URI: hp:/usb/HP_LaserJet_CP1025?serial=00000GF02F0ES
hp-check[3681]: info: :PPD: /etc/cups/ppd/HP_LaserJet_CP1025.ppd
hp-check[3681]: info: :PPD Description: HP LaserJet cp1025, hpcups 3.11.7, requires proprietary plugin
hp-check[3681]: info: :Printer status: printer HP_LaserJet_CP1025 is idle. enabled since jeu. 01 déc. 2011 20:11:14 CET
 ready to print

hp-check[3681]: info: :Required plug-in status: Installed
hp-check[3681]: info: :Communication status: Good
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :----------------------
hp-check[3681]: info: :| SANE CONFIGURATION |
hp-check[3681]: info: :----------------------
hp-check[3681]: info: :
hp-check[3681]: info: :'hpaio' in '/etc/sane.d/dll.conf'...
hp-check[3681]: info: :'hpaio' in '/etc/sane.d/dll.d/hplip'...
hp-check[3681]: info: :OK, found. SANE backend 'hpaio' is properly set up.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking output of 'scanimage -L'...
hp-check[3681]: info: :

No scanners were identified. If you were expecting something different,

check that the scanner is plugged in, turned on and detected by the

sane-find-scanner tool (if appropriate). Please read the documentation

which came with this software (README, FAQ, manpages).

hp-check[3681]: info: :
hp-check[3681]: info: :---------------------
hp-check[3681]: info: :| PYTHON EXTENSIONS |
hp-check[3681]: info: :---------------------
hp-check[3681]: info: :
hp-check[3681]: info: :Checking 'cupsext' CUPS extension...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking 'pcardext' Photocard extension...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking 'hpmudext' I/O extension...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :Checking 'scanext' SANE scanning extension...
hp-check[3681]: info: :OK, found.
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :
hp-check[3681]: info: :-----------------
hp-check[3681]: info: :| USB I/O SETUP |
hp-check[3681]: info: :-----------------
hp-check[3681]: info: :
hp-check[3681]: info: :Checking for permissions of USB attached printers...
hp-check[3681]: info: :
HP Device 0xb2a at 001:004:
hp-check[3681]: info: : Device URI: hp:/usb/HP_LaserJet_CP1025?serial=00000GF02F0ES
hp-check[3681]: info: : Device node: /dev/bus/usb/001/004
hp-check[3681]: info: : Mode: 0664
hp-check[3681]: info: :getfacl : suppression du premier << / >> des noms de chemins absolus

# file: dev/bus/usb/001/004

# owner: root

# group: lp

user::rw-

user:florent:rw-

group::rw-

mask::rw-

other::r--

hp-check[3681]: info: :
hp-check[3681]: info: :---------------
hp-check[3681]: info: :| USER GROUPS |
hp-check[3681]: info: :---------------
hp-check[3681]: info: :
hp-check[3681]: info: :florent adm dialout fax cdrom floppy tape audio dip video plugdev fuse lpadmin netdev admin sambashare

error: User needs to be member of group 'lp' to enable print, scan & fax.
hp-check[3681]: info: :User member of group 'lpadmin'.
hp-check[3681]: info: :
hp-check[3681]: info: :-----------
hp-check[3681]: info: :| SUMMARY |
hp-check[3681]: info: :-----------
hp-check[3681]: info: :
error: 12 errors and/or warnings.
hp-check[3681]: info: :
hp-check[3681]: info: :Please refer to the installation instructions at:
hp-check[3681]: info: :http://hplip.sourceforge.net/install/index.html

hp-check[3681]: info: :
hp-check[3681]: info: :Done.