title: Difference between JodaTime and Calendar for years before 1900
body: <p>I'm getting different values in milliseconds for the same date in past while using JodaTime lib and java.util.Calendar.
  For example for the first year AD </p>
  
  <pre><code>void test() {
      int year = 1;
      DateTime dt = new DateTime(year, 1,1,0,0,0,0);
      dt = dt.toDateTime(GregorianChronology.getInstance());
  
      Calendar cal = Calendar.getInstance();
      cal.clear();
      cal.set(year, 0, 1, 0, 0, 0);
  
      DateTime endDate = new DateTime(cal.getTimeInMillis());
      endDate = endDate.toDateTime(GregorianChronology.getInstance());
  
      System.out.println("JodaTime: " + dt);
      System.out.println("JodaTime, ms: " + dt.getMillis());
      System.out.println("Calendar: " + cal.getTime());
      System.out.println("Calendar, ms: " + cal.getTimeInMillis());
      System.out.println("JodaTime by Calendar: " + endDate);
  }
  </code></pre>
  
  <p>By default DateTime use ISOChronology and Calendar is GregorianCalendar (except TH and JA locales). So I set GregorianChronology, but nothing changed.
  Result of execution is</p>
  
  <pre><code>JodaTime:       0001-01-01T00:00:00.000+01:34:52
  JodaTime, ms:   -62135602492000
  Calendar:       Sat Jan 01 00:00:00 EET 1
  Calendar, ms:   -62135776800000
  JodaTime by Calendar:   0000-12-29T23:34:52.000+01:34:52
  </code></pre>
  
  <p>Could someone suggest am I wrong with something?</p>