Qt menuBar and Ubuntu Unity

# The following code is a severely reduced version of my application. Hopefully
# it demonstrates the following problem.

# Problem:
# An extra resize event is being created after the subwindow should be fully
# realized.

# Select New->SubWindow
# The extra resize event is printed to stdout.
# AFAIK, this only happens on Ubuntu(12.04)/Unity 2d or 3d

import sys
from PyQt4.QtCore import *
from PyQt4.QtGui import *
from PyQt4.QtCore import Qt as qt

class GView(QGraphicsView):
    def __init__(self, parent=None):
        super(GView, self).__init__(parent)
        self.setScene(QGraphicsScene(QRectF(0, 0, 100, 100)))
        self.scene().addRect(50, 50, 10, 10)
        self.setHorizontalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
        self.setVerticalScrollBarPolicy(Qt.ScrollBarAlwaysOff)
    def fitAll(self):
        r = QRectF()
        for item in self.scene().items():
            r = r.united(item.boundingRect())
        self.fitInView(r, qt.KeepAspectRatio)
    def resizeEvent(self, e):
        print "resize", e.size()
        super(GView, self).resizeEvent(e)


class AppWindow(QMainWindow):
    def __init__(self, parent=None):
        super(AppWindow, self).__init__(parent)
        self.mdiArea = QMdiArea(self)
        self.mdiArea.setHorizontalScrollBarPolicy(Qt.ScrollBarAsNeeded)
        self.mdiArea.setVerticalScrollBarPolicy(Qt.ScrollBarAsNeeded)
        self.setCentralWidget(self.mdiArea)

        # Comment the following four lines and click in the main window to
        # create a new subwindow. The extra resize event is not created.
        # So is the very presence of the menuBar creating the event?
        newMenu = self.menuBar().addMenu("&New")
        subWinAction = newMenu.addAction("&SubWindow")
        self.connect(subWinAction, SIGNAL("triggered(bool)"),
                     self.onSubWindow)

        self.statusBar()
    def onSubWindow(self, b=False):
        view = GView()
        self.addSubWindow(view)
        view.fitAll()
        print "no resize should follow this comment"
    def addSubWindow(self, view):
        self.mdiArea.addSubWindow(view)
        view.setAttribute(Qt.WA_DeleteOnClose)
        subWin = self.mdiArea.currentSubWindow()
        if subWin and not subWin.isMaximized():
            view.show()
        else:
            view.showMaximized()
    def mousePressEvent(self, e):
        self.onSubWindow()


if __name__ == '__main__':
    app = QApplication(sys.argv)
    mainWin = AppWindow()
    mainWin.show()
    app.exec_()