libgksu/gksu prevents preserving of environment variables when GTK dialog is displayed to enter password.

I am using a slightly modified /etc/sudoers file, to preserve a few environment variables to run GTK apps via sudo, and still have them accessible. However, it seems when one initially launches an app via gksu, for example /usr/bin/software-properties-gtk, and enters their password in the GTK dialog, these environment variables are not preserved. This is evident when using the Orca screen reader. It is not possible to move around the application and get speech feedback. On a second run however, when sudo knows about the previous password entry, and gksu displays no dialog, the environment variables are passed through just fine.

Attached is my /etc/sudoers file.

 affects ubuntu/libgksu