I’ve got error message:

elang:~# apt-get install lynx

Reading package lists… Done

Building dependency tree       

Reading state information… Done

lynx is already the newest version.

0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

27 not fully installed or removed.

After this operation, 0B of additional disk space will be used.

Setting up docbook-xml (4.5-5) …

update-xmlcatalog: error: entity already registered

dpkg: error processing docbook-xml (–configure):

 subprocess post-installation script returned error exit status 1

dpkg: dependency problems prevent configuration of scrollkeeper:

 scrollkeeper depends on docbook-xml (>= 4.2-11); however:

  Package docbook-xml is not configured yet.

dpkg: error processing scrollkeeper (–configure):

 dependency problems - leaving unconfigured

dpkg: dependency problems prevent configuration of bug-buddy:

 bug-buddy depends on scrollkeeper; however:

  Package scrollkeeper is not configured yet.

Actually this happened after I upgrade to Lenny from Etch. I found the brutallity problem solving from google at one of LinuxQuestions thread.

And I try it:

elang:~# apt-get remove docbook-xml

Reading package lists… Done

Building dependency tree       

Reading state information… Done

The following packages will be REMOVED:

  bug-buddy capplets-data docbook-xml fast-user-switch-applet gedit gnome-applets gnome-applets-data

  gnome-control-center gnome-core gnome-panel gnome-panel-data gnome-session gnome-system-monitor

  gnome-terminal gnome-user-guide gnome-utils grdesktop nautilus nautilus-cd-burner nautilus-data scrollkeeper

  software-properties-gtk synaptic update-manager update-notifier yelp zenity

0 upgraded, 0 newly installed, 27 to remove and 0 not upgraded.

27 not fully installed or removed.

After this operation, 153MB disk space will be freed.

Do you want to continue [Y/n]? Y

(Reading database … 103795 files and directories currently installed.)

Removing bug-buddy …

Removing nautilus-cd-burner …

Removing gnome-core …

Removing nautilus …

Removing gnome-session …

Removing gnome-applets …

Removing fast-user-switch-applet …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-panel …

Removing gnome-control-center …

Removing capplets-data …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-user-guide …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing yelp …

Removing zenity …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing update-notifier …

Removing update-manager …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing software-properties-gtk …

Removing synaptic …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing nautilus-data …

Removing grdesktop …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-utils …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-terminal …

Removing gnome-system-monitor …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-panel-data …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gnome-applets-data …

scrollkeeper-update: deferring update until scrollkeeper is configured

Removing gedit …

Removing scrollkeeper …

Removing docbook-xml …

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

update-xmlcatalog: error: entity not registered

Processing triggers for menu …

Processing triggers for man-db …

looks like it is solved. At least that error  messages not present anymore

elang:~# apt-get install lynx

Reading package lists… Done

Building dependency tree       

Reading state information… Done

lynx is already the newest version.

0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.