@Test
public void shouldPreserveOriginalCase() {

    Headers headers = new Headers();
    headers.setHeader("header", "Value");
    headers.setHeader("someOtherHeader", "123");
    assertThat(headersSerializer.serialize(headers), anyOf(
            is("someOtherHeader: 123\r\nheader: Value\r\n\r\n"),
            is("header: Value\r\nsomeOtherHeader: 123\r\n\r\n")
    ));
}