Can't style QHeaderView::section:selected in QSS stylesheet

[dictoon]

The title says it all: I seem unable to change the background color (or any other property) of a QHeaderView section using the QHeaderView::section:selected selector using Qt 4.7.0. Here's the relevant code:

QHeaderView::section:selected
{
    background-color: red;
}

QHeaderView::section:selected
{
    background-color: red;
}

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This is what I have now:

QHeaderViewSectionSelectedBefore.png

And this is what I would like to achieve (the selected section is highlighted):

QHeaderViewSectionSelectedAfter.png

According to the documentation, this ought to be possible:

QHeaderView: Supports the box model. The sections of the header view are styled using the ::section sub control. The section Sub-control supports the :middle, :first, :last, :only-one, :next-selected, :previous-selected, :selected, and :checked pseudo states.

Am I doing it right?

(I couldn't find anything on that subject in the bug database, and I don't have Qt 4.8 handy to check if the behavior is different.)

Cheers,
Franz