Bug#374979: tapping doesn't work in kde-applications for kde 3.5
Ah, it seems you have ksynaptics installed. Remove it because currently
ksynaptics is incompatible with a new synaptics driver. This should get
previous normal behaviour back. When this bug gets closed, feel free to
install ksynaptics again.
Thanks, this works!
NB: This is unrelated, but maybe you know how to make KDE _not_ to
interpret horizontal/vertical scrolling as 'back' or 'forward' button
events? I just can't find the setting for that.
(I managed to deactivate it for firefox via about:config, but can't find
the appropriate setting for kde and friends.)