Any luck with this?
I had something similar on mine before Christmas. The ball and socket joint on the base of the gear stick had come loose, so the stick was not connected to the arm that pulls the cable and allows you to change gears. Resulted in the stick being floppy and me not being able to get out of 5th (I was driving at the time)!
You can easily enough unbutton the gaitor on the gear stick and pull away the plastic around the base to get clear access to the bottom of the stick and have a look around.
I got the AA out to lever it back into place as I was at the side of the road and since then it's been OK, although there is a bit more play in the stick than there was before. I am planning to get it looked at during the upcoming service.
Anyone else had this before?