JBoss Cache leaks memory when used with FAIL_SILENTLY option

When using failSilently Option one entry per cache put is leaked to the 2 HashMaps in TransactionTable class.

See JBCACHE-1246.

This significantly effects Hibernate's (and thus EJB3's) usage of JBC as a 2nd Level Cache. Other standard AS usages of JBCare unaffected.