What is the proper (and/or best) way to write an hql query that involves comparison with BigDecimal.

Im using postgresql. Hibernate stores BigDecimal as a bytea;
however, the queries that I've written return an error message that indicate
hql is trying to compare a bytea with an int.

The java method that I'm using has two input parameter: lowValue and highValue, both of type BigDecimal.

<snippet>

String queryString = " select galaxy as galaxy where galaxy.size between "
+ lowvalue + " and " + highValue;

Query query = session.createQuery (queryString);
resultList = query.list()

</snippet>


Thanks for any suggestions.

Charlie