Criptografar user e password

<datasources>
  <xa-datasource>
    <max-pool-size>20</max-pool-size>
    <idle-timeout-minutes>2</idle-timeout-minutes>
    <jndi-name>DB</jndi-name>
    <track-connection-by-tx/>
    <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:@127.0.0.1:7000:ora9i</xa-datasource-property>
<!-- em vez de escrever o user, colocar aqui ele criptografado -->
    <xa-datasource-property name="User">user</xa-datasource-property>
    <xa-datasource-property name="Password">password</xa-datasource-property>
    <exception-sorter-class-name>org.jboss.resource.adapter.jdbc.vendor.OracleExceptionSorter</exception-sorter-class-name>
    <no-tx-separate-pools/>
  </xa-datasource>

  <mbean code="org.jboss.resource.adapter.jdbc.xa.oracle.OracleXAExceptionFormatter" 
         name="jboss.jca:service=OracleXAExceptionFormatter">
    <depends optional-attribute-name="TransactionManagerService">jboss:service=TransactionManager</depends>
  </mbean>

</datasources>