I was surprised at how easy it was.
You need to do the following:
1. Find your mouse’s address using ‘hcitool scan‘
2. Verify that you can pair the two devices using ‘sudo hidd –connect XX:XX:XX:XX:XX:XX‘
3. Edit /etc/default/bluetooth, uncomment the additional line with the HIDD_OPTIONS and set it to be
“–connect XX:XX:XX:XX:XX:XX –server”
4. Restart the service ‘bluetooth’
This works immediately after using the hardware button to enable/disable BT on my IBM Thinkpad. If I turn the mouse off, I need to press on the hardware button to disable/re-enable the bluetooth.