Statements in the HarvestDatabase are often not being closed after use

When running the TEST11B with the Derby that stresses the admin DB (a.k.a archive DB), we found that after moving the connectionpool system used by the harvestDatabase, ressources are not being released, if we do not closes the preparedStatents after use.

It might not be an issue with PostgreSQL or MySQL, but it certainly is with Derby. (See bug NAS-1997). Some of the problems we have experienced with Derby could be related to that.