QDockWidget separator

[A Former User]

Hi all,
i'm working with qt 4.8.4.
I need to style separator of QDockWidget, i know that with QSS QMainWindow::separator i can style separator. It works well only when QDockWidget hasn't fixed size.
@ qDock->widget()->setSizePolicy(QSizePolicy::Policy::Minimum,QSizePolicy::Policy::Minimum);
qDock->widget()->setMinimumHeight(0);
qDock->widget()->setMaximumHeight(5);
@
!http://www.qtcentre.org/attachment.php?attachmentid=9708&d=1382451351&thumb=1(Example )!

But if QDockWidget have fixed size, the color of separator is always default system.

@
qDock->widget()->setSizePolicy(QSizePolicy::Policy::Minimum,QSizePolicy::Policy::Minimum);
qDock->widget()->setMinimumHeight(0);
qDock->widget()->setMaximumHeight(0);
@
!http://www.qtcentre.org/attachment.php?attachmentid=9709&d=1382451353&thumb=1(Example )!

How can i mantain color also with fixed size?

Thank you

Marco