I'm using Qt 4.5.0

I use this code to change the color of a QButton:
Qt Code: 
  1. SigColorButton->setPalette(QPalette((Qt::GlobalColor)mainwindow->maincurve->signal_color));
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This works with Plastic and windows style but not with GTK style...

After compilation, when I run the app with "app -style plastic" or "app -style windows" it's ok. It's not ok when I try "app -style gtk".

OS is Linux, tried on OpenSUSE and Ubuntu. GTK2 development files are installed and Qt was configured to use GTK-style.
The GTK-style does work, problem is that I can not change the color of a QButton when using GTK style.

Any ideas?