An example ejb-jar.xml that shows how to override an @ejb reference.

ejb-jar.xml

<?xml version="1.0" ?>
<ejb-jar xmlns="http://java.sun.com/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://java.sun.com/xml/ns/javaee
                             http://java.sun.com/xml/ns/javaee/ejb-jar_3_1.xsd"
         version="3.1">
  <enterprise-beans>
    <session>
      <ejb-name>ReferencingBeanName</ejb-name>
      <ejb-local-ref>
        <ejb-ref-name>referencing.bean.pkg.ReferencingBean/fieldStoringReferencedBeanProxy</ejb-ref-name>
        <ejb-link>ReferencedBeanName</ejb-link>
      </ejb-local-ref>
    </session>
  </enterprise-beans>
</ejb-jar>