New users in admin group cannot use policykit

Binary package hint: policykit-1

New created users in admin, can't get privileges via policykit to do administrative tasks.
If I create a new administrator user with "adduser --ingroup admin username" is with the intention of he/she to can administrate the system, and he/she won't be able to do it if a policykit authentication is needed, because policykit asks for "root" password, and not for the user password.
Steps to reproduce:
1) Create a new admin user with "adduser --ingroup admin username".
2) Login with the new user.
3) Delete the old administrator user (installation user).
3) Try to administrate the system with any tool which requires policykit authentication.
4) You won't be able because the policykit dialog asks for the "root" password, not for your user password, and the old administrator account has been deleted.

New created administrator users should be able to do administrative tasks with policykit authentication.

ProblemType: Bug
DistroRelease: Ubuntu 11.04
Package: policykit-1 0.101-1ubuntu1
ProcVersionSignature: Ubuntu 2.6.38-8.42-generic 2.6.38.2
Uname: Linux 2.6.38-8-generic i686
Architecture: i386
Date: Tue Jun 7 00:59:46 2011
EcryptfsInUse: Yes
InstallationMedia: Kubuntu 11.04 "Natty Narwhal" - Release i386 (20110423)
ProcEnviron:
 LANGUAGE=
 PATH=(custom, user)
 LANG=es_ES.UTF-8
 SHELL=/bin/bash
SourcePackage: policykit-1
UpgradeStatus: No upgrade log present (probably fresh install)