Comment 1 for bug 287457

I've now managed to replicate the behaviour using 8.10 in a virtual machine (now that I've *finally* got USB working in Virtualbox). Consequently, I've also developed a workaround that gets Pystromo working.
Basically, you need to stop Xorg from using its evdev driver for input devices. We do this by modifying what HAL (Hardware Abstraction Layer) has to say about such devices:

1. Modify your /etc/X11/xorg.conf to add InputDevice sections for keyboard and mouse. I copied these sections from my current Hardy install, so you may not need all the keyboard Options, or may need to change some:

Section "InputDevice"
 Identifier "Generic Keyboard"
 Driver "kbd"
 Option "XkbRules" "xorg"
 Option "XkbModel" "pc105"
 Option "XkbLayout" "gb"
EndSection

Section "InputDevice"
 Identifier "Configured Mouse"
 Driver "mouse"
 Option "CorePointer"
EndSection

2. Place the attached 52-pystromo.fdi file in /usr/share/hal/fdi/policy/20thirdparty/

3. `sudo /etc/init.d/hal restart`

4. Log out (which will restart X), and when you log back in Pystromo should be able to grab the device nodes it needs.

NB: Be prepared to boot/switch to a console to revert any changes, in case this doesn't work and X doesn't start! I've done a lot of rooting around and messing about on my VM install, but AFAICT these four steps *should be* all that you need to do.