can't change printer setting in kubuntu karmic

Binary package hint: kdebase-workspace

My karmic kubuntu ssystem is connected to several printers via the
LPD/LPR protocol. These printer are listed when I click on the menu
System-Setting/printer-configuration/Server-Setting and check the box
"display shared printer" and "sharing printers"

However, there is no way to change the printer-setup. In particular, printing
is always one-sides, while all these printer are full-duplex and normally
do double-side printing, as prevuoissly (in kde3)

Note that normally changing (even adding) printer requires superuser privilege.
But there is no button to become superuser. Hence all printer options are
greyout meaning that it is impossible to change. The oly permissible change
is to define the default printer !

ProblemType: Bug
Architecture: amd64
Date: Fri Nov 20 16:24:57 2009
DistroRelease: Ubuntu 9.10
Package: systemsettings 4:4.3.2-0ubuntu7.1
ProcEnviron:
 LANGUAGE=
 PATH=(custom, no user)
 LANG=fr_FR.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.31-14.48-generic
SourcePackage: kdebase-workspace
Uname: Linux 2.6.31-14-generic x86_64