I've recently switched from Hibernat 4.2 to 4.3. In this switch we ran into a regression. Hibernat 4.3 fails with an IllegalArgumentException if a parameter with value null is assigned to a Temporal parameter (i.e. java.util.Date and others). See the following stacktrace (only Hibernate relevant part showing)

java.lang.IllegalArgumentException: Unexpected type [null] passed with TemporalType; expecting Date or Calendar
at org.hibernate.jpa.internal.QueryImpl$ParameterRegistrationImpl.bindValue(QueryImpl.java:318)
at org.hibernate.jpa.spi.BaseQueryImpl.setParameter(BaseQueryImpl.java:656)
at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:192)
at org.hibernate.jpa.spi.AbstractQueryImpl.setParameter(AbstractQueryImpl.java:49)