[vtkusers] vtkEventQtSlotConnect skips vtkCommand::LeftButtonReleaseEvent?

[Constantine Zakkaroff]

Hello ALL.

Strange issue: vtkEventQtSlotConnect does not trigger 
vtkCommand::LeftButtonReleaseEvent connection.

Here's how connections are created:

m_QtEventConections = vtkEventQtSlotConnect::New();

m_QtEventConections->Connect(qvtkWidget->GetRenderWindow()->GetInteractor(),
		vtkCommand::LeftButtonPressEvent,
		this,
		SLOT(processEvent(vtkObject*, unsigned long)));

m_QtEventConections->Connect(qvtkWidget->GetRenderWindow()->GetInteractor(),
		vtkCommand::LeftButtonReleaseEvent,
		this,
		SLOT(processEvent(vtkObject*, unsigned long)));

Both connections appear in the list when vtkEventQtSlotConnect is 
printed to std::cout, but process event only fires in the case of 
vtkCommand::LeftButtonPressEvent, not 
vtkCommand::LeftButtonReleaseEvent. Am I doing something wrong here?

Thanks for your help.

Regards,
Constantine