Enabling Brightness Control on User self-buil Kernel

[antoni_NT]

I got a problem when I use my newly built kernel.
When I first install fedora I choose xen kernel, and when I tried to upgrade Alsa Driver, I succeded.
But a problem when I use it is I cannot shutdown my laptop. But if I use basic kernel it works.

Now, I'm building my kernel (2.6.22.5) and I can shutdown, can upgrade Alsa Driver. But I cannnot control my LCD brightness. Why is this happen. When I modify the configuration I have carefully followed the xen config.
Why? Please someone, or maybe kernel hackers, help me!
What additional module do I need.