QTreeView: stylesheet :has-children pseudo selector doesn't works for the ::item pseudo-class

Trying to set a background color for items with children in a QTreeView using style sheet using QTreeView::item:has-children does not work.
It seems that the has-children pseudo-state is not supported for QTreeView::item.

Example code:

#include <QtGui>

int main(int argc, char *argv[])
{
QApplication app(argc, argv);

QDirModel model;
QTreeView tree;
tree.setModel(&model);

tree.setStyleSheet("QTreeView::item:has-children

");

// Demonstrating look and feel features
tree.setAnimated(false);
tree.setIndentation(20);
tree.setSortingEnabled(true);

tree.setWindowTitle(QObject::tr("Dir View"));
tree.resize(640, 480);
tree.show();

return app.exec();
}