Comment 10 for bug 330258

I encountered this same bug but found an alternative solution that I thought I would share. The script is export_x_info, detailed in the link below, that exports the dbus session address on startup to a file for use by my scripts

http://askubuntu.com/questions/42741/how-to-automatically-switch-monitors-with-my-laptop-dock/48627#48627

It was found in a thread on the Ubuntu forums: http://ubuntuforums.org/showthread.php?t=1076486