Michael Simons, in my opinion, your fix makes things worse. With Calendar-as-a-Date (or plain Date), foobar.getRefDate().getTime().toString() should return 00:00:00 in the users timezone. Nearly all JDBC drivers do this. Your test case's entity returns the following refDate toString on most JDBC drivers, both before and after

Tue Oct 22 00:00:00 EDT 2013

Obviously w/ your fix, an hour can be there depending on the offset. Like Steve said, what we were shooting for really is the expected behavior.