I want to first state that I have only tested this on my Dell D620 & D820 and do not know what else it will work on. I do remember several people complaining about this problem, mainly dell users.
The problem: When using BT2 with my notebook lid closed the LCD will not turn off.
The solution: Use of a script to check the state of the lid and either turn on or off the LCD appropriately.
#From konsole type:
Now you should have a file called lid located @ /etc/acpi/events/ and a file called lid.sh located @ /etc/acpi/
if grep -q open /proc/acpi/button/lid/LID/state
XAUTHORITY="$( ps -C xinit f|tail -n 1|sed s/.*-auth\ //|sed s/serverauth.*/Xauthority/ )" /usr/bin/xset -display :0.0 dpms force on
XAUTHORITY="$( ps -C xinit f|tail -n 1|sed s/.*-auth\ //|sed s/serverauth.*/Xauthority/ )" /usr/bin/xset -display :0.0 dpms force off
Thanks go to my Google'Fu™