To use the PostGIS types, you must:
- have the postgis.jar in your CLASSPATH
- have a PostgreSQL JDBC Connection instance

  Connection conn = new Connection();
  ((org.postgresql.Connection)conn).addDataType("geometry","org.postgis.PGgeometry");
  ((org.postgresql.Connection)conn).addDataType("box3d","org.postgis.PGbox3d");

-