Synaptics button - movement issues

[Riccardo Mottola <riccardo.mottola%libero.it@localhost>]

Hello,

I have a laptop with a Synaptics touchpad which has "integrated" 
buttons, that is the lower part of the touchpad has buttons, but it also 
makes part of the scroll surface.
I have issues that when clicking on the buttons, the touch movement 
remains active and makes the cursor jump around. This makes it very had 
to click on something and impossible to click-drag on a menu or 
context-menu!

Can this be "fixed" with some sysctl setting?

hw.synaptics.up_down_emulation = 3
hw.synaptics.up_down_motion_delta = 1
hw.synaptics.gesture_move = 200
hw.synaptics.gesture_length = 20
hw.synaptics.edge_left = 1632
hw.synaptics.edge_right = 5312
hw.synaptics.edge_top = 4288
hw.synaptics.edge_bottom = 1568
hw.synaptics.edge_motion_delta = 32
hw.synaptics.finger_high = 35
hw.synaptics.finger_low = 20
hw.synaptics.two_fingers_emulation = 0
hw.synaptics.scale_x = 16
hw.synaptics.scale_y = 16
hw.synaptics.scale_z = 32
hw.synaptics.max_speed_x = 32
hw.synaptics.max_speed_y = 32
hw.synaptics.max_speed_z = 2
hw.synaptics.movement_threshold = 4
hw.synaptics.movement_enable = 1
hw.synaptics.button_boundary = 2288
hw.synaptics.button2_edge = 2858
hw.synaptics.button3_edge = 4085
hw.synaptics.finger_scroll-min = 13
hw.synaptics.finger_scroll-max = 14
hw.synaptics.finger_scroll-hysteresis = 30
hw.synaptics.aux_mid_button_scroll = 1

I have not seen somee specific setting, but maybe the button 
boundaris/edges control this behavioiur and are detected wrong?

Riccardo