hibernate.cfg.xml includes the following configuration items that may be modified to support other databases or application servers.

<!-- sql dialect -->
<property name="hibernate.dialect">org.hibernate.dialect.HSQLDialect</property>

<property name="hibernate.cache.provider_class">
  org.hibernate.cache.HashtableCacheProvider
</property>

<!-- DataSource properties (begin) -->
<property name="hibernate.connection.datasource">java:comp/env/jdbc/JbpmDataSource</property>
<!-- DataSource properties (end) -->

<!-- JTA transaction properties (begin) -->
<property name="hibernate.transaction.factory_class">
  org.hibernate.transaction.JTATransactionFactory
</property>
<property name="hibernate.transaction.manager_lookup_class">
  org.hibernate.transaction.JBossTransactionManagerLookup
</property>
<!-- JTA transaction properties (end) -->

<!-- CMT transaction properties (begin) ===
<property name="hibernate.transaction.factory_class">
  org.hibernate.transaction.CMTTransactionFactory
</property>
<property name="hibernate.transaction.manager_lookup_class">
  org.hibernate.transaction.JBossTransactionManagerLookup
</property>
==== CMT transaction properties (end) -->

You may replace the hibernate.dialect with one that corresponds to your database management system. The Hibernate reference guide enumerates the available database dialects in section 3.4.1 SQL dialects.

HashtableCacheProvider can be replaced with other supported cache providers. Refer to section 19.2 The second level cache of the Hibernate manual for a list of the supported cache providers.

The JBossTransactionManagerLookup may be replaced with a strategy appropriate to applications servers other than JBoss. See section 3.8.1 Transaction strategy configuration to find the lookup class that corresponds to each application server.

Note that the JNDI name used in hibernate.connection.datasource is, in fact, a resource manager reference, portable across application servers. Said reference is meant to be bound to an actual data source in the target application server at deployment time. In the included jboss.xml descriptor, the reference is bound to java:JbpmDS.

Out of the box, jBPM is configured to use the JTATransactionFactory. If an existing transaction is underway, the JTA transaction factory uses it; otherwise it creates a new transaction. The jBPM enterprise beans are configured to delegate transaction management to the container. However, if you use the jBPM APIs in a context where no transaction is active (say, in a web application), one will be started automatically.

If your own EJBs use container-managed transactions and you want to prevent unintended transaction creations, you can switch to the CMTTransactionFactory. With that setting, Hibernate will always look for an existing transaction and will report a problem if none is found.