code: @Test public void testMultipleTo() throws Exception {
    smtpAppender.setLayout(buildPatternLayout(loggerContext));
    smtpAppender.addTo("Test <test@example.com>, other-test@example.com");
    smtpAppender.start();
    Logger logger=loggerContext.getLogger("test");
    logger.addAppender(smtpAppender);
    logger.debug("hello");
    logger.error("en error",new Exception("an exception"));
    waitUntilEmailIsSent();
    List<WiserMessage> wiserMsgList=WISER.getMessages();
    assertNotNull(wiserMsgList);
    assertEquals(numberOfOldMessages + 3,wiserMsgList.size());
  }
  