Laptop display stays on with lid closed

I only noticed this now, thought it is a hardware
glitch. My laptop display - and its backlight -
stay on when I close the lid. Shouldn't it be
turned off like in an OS-independent way?..

Anyway, mailing lists say that at least some lap-
tops keep their display on with closed lid, I'm
not sure about backlight though. I don't need the
lid to trigger any Sx state, can I just get the
display to turn off? BTW, acpi notices the lid
closed event, so the trigger must be working.

If not, I would appreciate a way to turn it off
with some script, so that I can run it manually.

My laptop is the now infamous Fujitsu-Siemens
Amilo Pa 1510 [1].

[1] http://www.fujitsu-siemens.com/home/products/notebooks/amilo_pa_1510.html

Thanks!