JDBC Driver Modifies Calendar passed into setTimestamp() creates problem with Hibernate

There appears to be a possible problem with PreparedStatement's

setTimestamp(int parameterIndex, Timestamp x, Calendar cal)

The Calendar object passed into this method is modified by
PostgreSQL's JDBC driver.  This causes problems with Hibernate.  I
offered a solution for hibernate to clone the calendar before calling
the method but Gavin King of Hibernate believes it's the JDBC driver's
problem.  Here is the link to the hibernate bug discussed.

http://opensource.atlassian.com/projects/hibernate/browse/HHH-405

Mike