QTreewidget stylesheet problem: second column

[trallallero]

I'm facing a problem using stylesheets with QTreeWidget.

I'm working with Qt 4.7 and these are the stylesheets I'm using, got from:
http://doc.qt.nokia.com/4.8/stylesheet-examples.html

QTreeView {
     show-decoration-selected: 1;
 }
 
 QTreeView::item {
     border: 1px solid #d9d9d9;
     border-top-color: transparent;
     border-bottom-color: transparent;
 }
 
 QTreeView::item:hover {
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #e7effd, stop: 1 #cbdaf1);
     border: 1px solid #bfcde4;
 }
 
 QTreeView::item:selected {
     border: 1px solid #567dbc;
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #e7effd, stop: 1 #cbdaf1);
 }
 
 QTreeView::item:selected:active{
     border: 1px solid yellow;
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #6ea1f1, stop: 1 #567dbc);
 }
 
 QTreeView::item:selected:!active {
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #6b9be8, stop: 1 #577fbf);
 }

QTreeView {
     show-decoration-selected: 1;
 }

 QTreeView::item {
     border: 1px solid #d9d9d9;
     border-top-color: transparent;
     border-bottom-color: transparent;
 }

 QTreeView::item:hover {
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #e7effd, stop: 1 #cbdaf1);
     border: 1px solid #bfcde4;
 }

 QTreeView::item:selected {
     border: 1px solid #567dbc;
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #e7effd, stop: 1 #cbdaf1);
 }

 QTreeView::item:selected:active{
     border: 1px solid yellow;
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #6ea1f1, stop: 1 #567dbc);
 }

 QTreeView::item:selected:!active {
     background: qlineargradient(x1: 0, y1: 0, x2: 0, y2: 1, stop: 0 #6b9be8, stop: 1 #577fbf);
 }

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Everything works fine if I select an item in column 1, but when I click an item in column 2, it's not blue highlighted.
The only thing you can see are the dots around the item.

Why ?