I can not click on the drop-down gnome-brigntness-applet

Binary package hint: gnome-power-manager

On Ubuntu 9.10 beta1 when i try to scroll brightness-applet icon with mouse, brightness is changing correctly and when i click the icon the drop-down appears. But when I click on the drop-down to change the brightness, disappears.
In addition, sometimes the drop-down appears in the corner of the screen.
I can not take a screenshot with the drop-down.

ProblemType: Bug
Architecture: i386
Date: Sat Mar 20 12:58:44 2010
DistroRelease: Ubuntu 10.04
ExecutablePath: /usr/lib/gnome-power-manager/gnome-brightness-applet
GnomeSessionIdleInhibited: No
GnomeSessionInhibitors: None
GnomeSessionSuspendInhibited: No
LiveMediaBuild: Ubuntu 10.04 "Lucid Lynx" - Beta i386 (20100318)
MachineType: ASUSTeK Computer INC. 1000H
Package: gnome-power-manager 2.29.91-0ubuntu6
ProcCmdLine: initrd=/ubninit file=/cdrom/preseed/hostname.seed boot=casper quiet splash -- BOOT_IMAGE=/ubnkern
ProcEnviron:
 LANG=en_US.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Ubuntu 2.6.32-16.25-generic
SourcePackage: gnome-power-manager
Uname: Linux 2.6.32-16-generic i686
dmi.bios.date: 10/21/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: 2204
dmi.board.asset.tag: To Be Filled By O.E.M.
dmi.board.name: 1000H
dmi.board.vendor: ASUSTeK Computer INC.
dmi.board.version: x.xx
dmi.chassis.asset.tag: 0x00000000
dmi.chassis.type: 10
dmi.chassis.vendor: ASUSTek Computer INC.
dmi.chassis.version: x.x
dmi.modalias: dmi:bvnAmericanMegatrendsInc.:bvr2204:bd10/21/2009:svnASUSTeKComputerINC.:pn1000H:pvrx.x:rvnASUSTeKComputerINC.:rn1000H:rvrx.xx:cvnASUSTekComputerINC.:ct10:cvrx.x:
dmi.product.name: 1000H
dmi.product.version: x.x
dmi.sys.vendor: ASUSTeK Computer INC.