When installing to JBoss and chosing oracle as a database, you can see that the JDBC properties in the datasource config are not replaced:

less server/default/deploy/jbpm/jbpm-oracle-ds.xml

<datasources>
<xa-datasource>
<jndi-name>JbpmDS</jndi-name>
<!-- uncomment to enable interleaving <interleaving/> -->
<isSameRM-override-value>false</isSameRM-override-value>
<xa-datasource-class>oracle.jdbc.xa.client.OracleXADataSource</xa-datasource-class>
<xa-datasource-property name="URL">jdbc:oracle:thin:${jdbc.oracle.username}/${jdbc.oracle.password}@${jdbc.oracle.serv
er}:${jdbc.oracle.port}:${jdbc.oracle.database}</xa-datasource-property>
<xa-datasource-property name="User">jbpmtest</xa-datasource-property>
<xa-datasource-property name="Password">jbpmtest</xa-datasource-property>
<!-- Uses the pingDatabase method to check a connection is still valid before handing it out from the pool -->
<!--valid-connection-checker-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleValidConnectionChecker</valid-con
nection-checker-class-name-->
<!-- Checks the Oracle error codes and messages for fatal errors -->
<exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name
>