title: Error converting long to Timestamp
body: <p>I'm constructing a java.sql.Timestamp using a long. Sometimes it gets it right other times it gets it wrong! e.g.</p>
  
  <p>76875 gives a Timestamp of "1970-01-01 01:01:16.875"</p>
  
  <p>Where has the extra hour come from? The problem arises and then goes away of its own accord giving:</p>
  
  <p>"1970-01-01 00:01:16.875".</p>
  
  <p>The bit of code causing the problem is running on Google appengine, could it be messing something up with TimeZones? I have tried to identify a pattern but have not managed as yet.</p>