Column layout buttons yield unexpected 0px spacing

[ftessier]

When selecting multiple objects, the expected behaviour of clicking a "Column layout" button is, in all graphical layout programs I use, a "distribute" action, meaning the objects are distributed with equal spacing between the top and bottom object. Currently, the spacing is set at 0px.

Eventually, it would also be great if the horizontal position of each objects remained unchanged upon applying the vertical layout, and conversely, if that is possible.