This works for me, however, instead of looking for the device `TPPS/2 Elan Trackpoint`, I had to use the id of `TrackPoint Keyboard 2`. The downside of this fix is that pasting with the middle button does not work anymore.
C. Martınez. Proc. 6th ACMSIAM Workshop on Algorithm Engineering and Experiments and 1st ACM-SIAM Workshop on Analytic Algorithmics and Combinatorics, page 224--228. (2004)