EasyMock : java.lang.IllegalStateException: 1 matchers expected, 2 recorded

I am having a problem with EasyMock 2.5.2 and JUnit 4.8.2 (running through Eclipse). I have read all the similar posts here but have not found an answer. I have a class containing two tests which test the same method. I am using matchers.

1. Each test passes when run alone.
2. The first test always passes - this is true if I switch the order of the tests in the file.

Here is a simplified version of the test code:

private Xthing mockXthing;
private MainThing mainThing;

@Before
public void setUp() {
    mockXthing = EasyMock.createMock(Xthing.class);
    mainThing = new MainThing();
    mainThing.setxThing(mockXthing);
}

@After
public void cleanUp() {
    EasyMock.reset(mockXthing);
}

@Test
public void testTwo() {
    String abc = "abc";
    EasyMock.expect(mockXthing.doXthing((String) EasyMock.anyObject())).andReturn(abc);
    EasyMock.replay(mockXthing);
    String testResult = mainThing.testCallingXthing((Long) EasyMock.anyObject());
    assertEquals("abc", testResult);
    EasyMock.verify(mockXthing);
}

@Test
public void testOne() {
    String xyz = "xyz";
    EasyMock.expect(mockXthing.doXthing((String) EasyMock.anyObject())).andReturn(xyz);
    EasyMock.replay(mockXthing);
    String testResult = mainThing.testCallingXthing((Long) EasyMock.anyObject());
    assertEquals("xyz", testResult);
    EasyMock.verify(mockXthing);
}

The second (or last) test always fails with the following error:

java.lang.IllegalStateException: 1 matchers expected, 2 recorded

Any insight to this would be greatly appreciated.

Thanks, Anne