tst_QGraphicsEffect fails on Mac OS X 10.7

********* Start testing of tst_QGraphicsEffect *********
Config: Using QTest library 4.8.3, Qt 4.8.3 
PASS   : tst_QGraphicsEffect::initTestCase()
PASS   : tst_QGraphicsEffect::setEnabled()
PASS   : tst_QGraphicsEffect::source()
PASS   : tst_QGraphicsEffect::boundingRectFor()
PASS   : tst_QGraphicsEffect::boundingRect()
PASS   : tst_QGraphicsEffect::boundingRect2()
PASS   : tst_QGraphicsEffect::draw()
PASS   : tst_QGraphicsEffect::opacity()
PASS   : tst_QGraphicsEffect::grayscale()
PASS   : tst_QGraphicsEffect::colorize()
PASS   : tst_QGraphicsEffect::drawPixmapItem()
PASS   : tst_QGraphicsEffect::deviceCoordinateTranslateCaching()
PASS   : tst_QGraphicsEffect::inheritOpacity()
PASS   : tst_QGraphicsEffect::dropShadowClipping()
FAIL!  : tst_QGraphicsEffect::childrenVisibilityShouldInvalidateCache() Compared values are not the same 
   Actual (parent.nbPaint): 2
   Expected (1): 1 
   Loc: [tst_qgraphicseffect.cpp(693)]
FAIL!  : tst_QGraphicsEffect::prepareGeometryChangeInvalidateCache() Compared values are not the same 
   Actual (item->nbPaint): 2
   Expected (1): 1 
   Loc: [tst_qgraphicseffect.cpp(721)]
PASS   : tst_QGraphicsEffect::graphicsEffectUpdateShouldNotInvalidateGraphicsItemCache()
FAIL!  : tst_QGraphicsEffect::graphicsEffectUpdateShouldInvalidateParentGraphicsEffect() Compared values are not the same 
   Actual (parent.nbPaint): 2
   Expected (1): 1 
   Loc: [tst_qgraphicseffect.cpp(805)]
FAIL!  : tst_QGraphicsEffect::itemHasNoContents() Compared values are not the same 
   Actual (child->nbPaint): 2
   Expected (1): 1 
   Loc: [tst_qgraphicseffect.cpp(845)]
PASS   : tst_QGraphicsEffect::cleanupTestCase()
Totals: 16 passed, 4 failed, 0 skipped
********* Finished testing of tst_QGraphicsEffect *********