I have two possibly related problems.

Since a few days ago any attempt to use my ThinkOutside bluetooth
keyboard causes N800 reboot. More precisely, I run OS2008
dual boot (either from flash or from internal memory card).
The keyboard works fine when N800 is booted from flash. When
running from the memory card, pairing is established but even
one keystroke causes N800 to reboot.

In my attempt to isolate the problem I tried using flasher to disable
the r&d mode. Flasher now hangs with "Unable to find suitable USB
device". I run flasher as root with "./flasher-3.0 --disable-rd-mode -R",
the usb icon shows up in the upper right corner after the N800 is
turned on and nothing else happens. When I pull out the USB cable
the boot process continues. I suspect that it is the problem with
my Debian (unstable) handling of USB.

Other than that everything seems to be working fine. I will appreciate any help with diagnosing/fixing the problem(s).

First off all the keyboard was bluetooth not USB. Sorry!

I made it work again by recloning the working OS from internal
flash to the memory card. Had to restore some stuff that was not
present on the internal flash but the keyboard is working well
again.