How do I enable Drag Lock buttons on my Kensington Expert Mouse trackball) in Ubuntu 12.04? I new how in Ubuntu 9.10, but have forgotten how. A disability prevents me from using a normal mouse, and I really need drag lock on the trackball. I used xev to confirm that Ubuntu sees all the buttons. I just need to assign draglock to button 2 for button 1, or assign button to as master draglock button.
In 9.10 the solution involved creating an FDI file in the HAL>Policies folder. In 12.04 it appears to be adding apprpriate "Option" commands to the xoeg.conf file. I can't seem to find the appropriate "Device Identifier" for my mouse.
In 9.10 I found it using lsusb -v.
Any help greatly appreciated.