Animators in StackView transitions don't seem to work

import QtQuick 2.4
import QtQuick.Window 2.0
import Qt.labs.controls 1.0

ApplicationWindow {
    id: root
    width: 480
    height: 320
    visible: true

    StackView {
        id: stackView
        initialItem: redRectComponent
        anchors.fill: parent

        Transition {
            id: enterTransition

            OpacityAnimator {
                from: 0
                to: 1
                duration: 1000
                easing.type: Easing.OutCubic
            }
        }

        Transition {
            id: exitTransition

            OpacityAnimator {
                from: 1
                to: 0
                duration: 1000
                easing.type: Easing.OutCubic
            }
        }

        pushEnter: enterTransition
        pushExit: exitTransition
        popEnter : enterTransition
        popExit : exitTransition
        replaceEnter : enterTransition
        replaceExit : exitTransition
    }

    Component {
        id: redRectComponent

        Rectangle {
            id: redRect
            color: "red"

            MouseArea {
                anchors.fill: parent
                onClicked: stackView.push(greenRectComponent)
            }
        }
    }

    Component {
        id: greenRectComponent

        Rectangle {
            id: greenRect
            color: "green"
        }
    }
}