reference id="jNDIContextManager" interface="org.osgi.service.jndi.JNDIContextManager" availability="mandatory"></reference>

	<bean id="userDbDataSource" class="com.atomikos.jdbc.AtomikosDataSourceBean"
		init-method="init" destroy-method="close">
		<property name="uniqueResourceName" value="userDb" />
		<property name="xaDataSourceClassName" value="org.apache.derby.jdbc.EmbeddedXADataSource" />
		<property name="xaProperties">
			<props>
				<prop key="databaseName">/tmp/userDb</prop>
				<prop key="createDatabase">create</prop>
			</props>
		</property>
		<property name="minPoolSize" value="1" />
		<property name="maxPoolSize" value="5" />
		<property name="borrowConnectionTimeout" value="10000" />
	</bean>
	<service ref="userDbDataSource" interface="javax.sql.DataSource">
		<service-properties>
			<entry key="osgi.jndi.service.name" value="userDb" />
		</service-properties>
	</service>

String persistanceUnit = (String) arg0.getProperty(EntityManagerFactoryBuilder.JPA_UNIT_NAME);
EntityManagerFactoryBuilder emfBuilder = (EntityManagerFactoryBuilder) context.getService(arg0); 
//Get the JNDIContextManager service: It would be better if it worked ^^
ServiceReference ref = context.getServiceReference(JNDIContextManager.class.getName());
//Get the DataSource object by the 'osgi' schema, using JNDI to scan the Service Registry
JNDIContextManager JNDIContextManager = (JNDIContextManager) context.getService(ref);
try {
	Context JNDIContext = JNDIContextManager.newInitialContext();
DataSource datasource=null;
	datasource=
			(DataSource)  JNDIContext.lookup("osgi:service/"+DataSource.class.getName()+"/(osgi.jndi.service.name="+persistanceUnit.replace("Pu", "Db")+")");
	if(datasource == null)
		throw new Exception("DataSource has not been found");