screen brightness set at minimun at boot

[jian1505]

I'm using kubuntu 9.04, kernel 2.6.30, kde4.3.
This problem also appeared with previous kernels and kde4 versions.
Sometimes, without any apparent reason, during boot process screen brightness gets dimmed all way down and after logon, adjusting the brightness with battery plasmoid doesn't work. Adjusting the brightness with keyboard shortcut 'Fn+brightnessup' works instead.
I'm not sure whether this is a kubuntu related problem or kde related problem, but if i restart hal by executing '/etc/init.d/hal restart' from the console, brightness and battery plasmoid starts again working as usual.

Thank you.

ProblemType: Bug
Architecture: amd64
DistroRelease: Ubuntu 9.04
MachineType: Acer TravelMate 5720
Package: usplash 0.5.31
ProcCmdLine: root=UUID=e65d650d-2591-4861-bd44-413ff5c1e214 ro quiet splash
ProcEnviron:
 LANGUAGE=
 PATH=(custom, user)
 LANG=it_IT.UTF-8
 SHELL=/bin/bash
ProcVersionSignature: Error: [Errno 2] Nessun file o directory: '/proc/version_signature'
SourcePackage: usplash
UsplashConf:
 # Usplash configuration file
 # These parameters will only apply after running update-initramfs.

 xres=1280
 yres=800