Problem with unified tool bar on Mac OS X

On OS X I have a problem with placing widgets on window tool bar when unifiedTitleAndToolBarOnMac flag is set. Looks like some kind of spacer item or stretch is placed on the right side of the tool bar, so all my widgets and buttons are moved to the left.
I've tried to create a frame with size policy I need (adding stretches and spacer items to the corresponding layout), but unfortunatly it doesn't work.
Setting fixed size to this frame works properly but this is not good to calculate the frame size every time tool bar is resizing =( Hope there's another way to do it...

Perhaps you could add a dummy plain QWidget with expanding size policy in front?