I'm unable to access IdentitySessionFactory from a custom portlet (located outside of the jboss sar)

In jboss-server.xml I have the following set:

<transaction>
 <trans-attribute>Required</trans-attribute>
 </transaction>
 <service>
 <service-name>UserModule</service-name>
 <service-class>org.jboss.portal.identity.UserModule</service-class>
 <service-ref>:service=Module,type=User</service-ref>
 </service>

In my portlet I'm doing this:

 SessionFactory identitySessionFactory = (SessionFactory) new InitialContext().lookup(
 "java:/portal/IdentitySessionFactory");

The above returns null (however the jndi is listing in the jmx console)

Any ideas?