OF-898: Adding unit test that tests for the problem.

src/test/java/org/jivesoftware/util/XMPPDateTimeFormatTest.java

 package org.jivesoftware.util;
 
 import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
 
 import java.text.DateFormat;
 import java.text.ParseException;
@@ -27,4 +28,46 @@ public class XMPPDateTimeFormatTest {
 		String date = df.format(parsedDate);
 		assertEquals(date, "2013-01-25T18:07:22.768+0000");
 	}
+
+    @Test
+    public void testFormatNoSecondFractions() throws Exception
+    {
+        // Setup fixture
+        final String testValue = "2015-03-19T22:54:15+00:00"; // Thu, 19 Mar 2015 22:54:15 GMT
+
+        // Execute system under test
+        final Date result = xmppDateTimeFormat.parseString(testValue);
+
+        // Verify results
+        long expected = 1426805655000L; // Epoch value of Thu, 19 Mar 2015 22:54:15 GMT
+        assertEquals( expected, result.getTime() );
+    }
+
+    @Test
+    public void testFormatThreeSecondFractions() throws Exception
+    {
+        // Setup fixture
+        final String testValue = "2015-03-19T22:54:15.841+00:00"; // Thu, 19 Mar 2015 22:54:15.841 GMT
+
+        // Execute system under test
+        final Date result = xmppDateTimeFormat.parseString(testValue);
+
+        // Verify results
+        long expected = 1426805655841L; // Epoch value of Thu, 19 Mar 2015 22:54:15.841 GMT
+        assertEquals( expected, result.getTime() );
+    }
+
+    @Test
+    public void testFormatManySecondFractions() throws Exception
+    {
+        // Setup fixture
+        final String testValue = "2015-03-19T22:54:15.841473+00:00"; // Thu, 19 Mar 2015 22:54:15.841473 GMT
+
+        // Execute system under test
+        final Date result = xmppDateTimeFormat.parseString(testValue);
+
+        // Verify results
+        long expected = 1426805655841L; // Epoch value of Thu, 19 Mar 2015 22:54:15 GMT
+        assertEquals( expected, result.getTime() );
+    }
 }