How to move nodes in a treeGrid

I want to programatically move a node in a treeGrid to THE SAME PARENT but to another position. With other words, I want to *reorder* the children of a parent programatically.

This doesn't work:
tree.move(node, parent, newPosition);

Since, as the docs say, it is intended to move the node to ANOTHER parent. So, nothing happens. How to achieve this ?

Using smartgwt 5.0p 28.06 power.