ThinkPad T30, ACPI: backlight stays on during suspend

[Steven Ihde <x-debian-laptop@hamachi.dyndns.org>]

I have a ThinkPad T30 I just installed with the latest stuff from
testing.  When I try to suspend with ACPI (echo "3" >
/proc/acpi/sleep), the laptop appears to suspend, but the display
backlight stays on.  If I try blanking the display through some other
means (such as xset dpms or setterm -power), the backlight comes back
on as soon as the ACPI sleep process starts.

Is this a lost cause, or has anybody ever encountered and resolved
this issue?

APM suspend appears to work OK, but I'd rather use ACPI if I could get
it working.  Note, however, that I had to upgrade to a kernel compiled
from kernel-source-2.6.8=2.6.8-7, because 2.6.8-3 through 2.6.8-6 had
a patch that broke even APM suspend (see the kernel-source-2.6.8-7
changelog for details and a reference to bugs).  The precompiled
kernel images in testing and unstable (for i686) are still compiled
from 2.6.8-3.

Thanks,

Steve