first thing after installation was getting the trackpoint scroll button working therefore created the file .xsessionrc in the home-directory with the following content

xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Wheel Emulation" 8 1
xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Wheel Emulation Button" 8 2
xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Wheel Emulation Timeout" 8 200
xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Wheel Emulation Axes" 8 6 7 4 5
xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Middle Button Emulation" 8 1
xinput set-int-prop "TPPS/2 IBM TrackPoint" "Evdev Middle Button Timeout" 8 50

after logging off and on again the trackpoint scolling works …