SignalSpy in QtQuickTest cannot handle target switching properly

import QtQuick 1.0
import QtTest 1.0

TestCase {
    id: spyTest
    name:  "SpyTest"

    SignalSpy {
        id: spy
    }

   function test_spy_data() {
        return [
            {tag: "round 1"},
            {tag: "round 2"}
        ]
    }
    function test_spy(data) {
        var obj = Qt.createQmlObject(
                "import QtQuick 1.0 \n"
                 + "Item {\n"
                 + "  signal dummySignal\n"
                 + "  property alias timer: dummyTimer\n"
                 + "  Timer {\n"
                 + "    id: dummyTimer\n"
                 + "    interval: 200; repeat: true\n"
                 + "    onTriggered: {parent.dummySignal();console.log(\"dummyTimer signaled!\");}\n"
                 + "  }\n"
                 + "}\n",
                 spyTest);

        spy.target = obj;
        spy.signalName = "dummySignal";
        spy.clear();
        compare(spy.count, 0);

        obj.timer.start();
        spyTest.wait(500);
        compare(spy.count, 2);
        obj.timer.stop();
    }
}

********* Start testing of qmlexample *********
Config: Using QTest library 5.0.0, Qt 5.0.0
PASS   : SpyTest::initTestCase()
QDEBUG : SpyTest::test_spy(round 1) dummyTimer signaled!
QDEBUG : SpyTest::test_spy(round 1) dummyTimer signaled!
QWARN  : SpyTest::test_spy(round 2) ---/imports/QtTest/SignalSpy.qml:95: Error: Function.prototype.disconnect: target is not a function
QDEBUG : SpyTest::test_spy(round 2) dummyTimer signaled!
QDEBUG : SpyTest::test_spy(round 2) dummyTimer signaled!
FAIL!  : SpyTest::test_spy(round 2) Compared values are not the same
   Actual (): 0
   Expected (): 2