Can't adjust brightness on Acer Aspire 5738 running Karmic. The same happened under Jaunty. The screen never seems to reach its full brightness and it flickers.

The notify osd shows a bright bar indicating the screen brightness increasing or decreasing when I use the fn key + the corresponding keys for increasing or reducing the screen brightness, but the screen always stays the same.

I can move the arrow in the brightness applet in the Gnome panel up and down, but nothing happens, either.

I think I'll report a bug.