Battery tab is not shown in GNOME Power Preferences panel when using laptop

Binary package hint: gnome-power-manager

Description: Ubuntu lucid (development branch)
Release: 10.04
Using Alpha 2

On my laptop, the "On Battery" tab is not displayed in the gnome-power-preferences window. The battery is always physically present in the laptop.

Steps to reproduce:
1. Boot laptop
2. Log in
3. Select System->Preferences->Power Management

Actual Result:
Only the "On AC Power" and "General" tabs appear in the window.

Expected Result:
The "On Battery" tab should also be displayed.

Reproducibility:
Always

ProblemType: Bug
Architecture: i386
Date: Tue Jan 19 07:28:21 2010
DistroRelease: Ubuntu 10.04
InstallationMedia: Ubuntu 10.04 "Lucid Lynx" - Alpha i386 (20100113)
Package: gnome-power-manager 2.28.1-0ubuntu3
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.32-10.14-generic
SourcePackage: gnome-power-manager
Tags: lucid
Uname: Linux 2.6.32-10-generic i686