I can't setup my jndi.properties to access remote EJBs on Jboss 5

An alternative way to do this is to configure a org.jboss.naming.ExternalContext MBean in your jboss-service.xml file:

<mbean code="org.jboss.naming.ExternalContext" 
       name="jboss.jndi:service=ExternalContext,jndiName=external/server2">
    <attribute name="JndiName">external/server2</attribute>
    <attribute name="Properties">
        java.naming.factory.initial=org.jnp.interfaces.NamingContextFactory
        java.naming.provider.url=jnp://10.90.0.91:1099
        <!-- other properties as needed -->
    </attribute>
    <attribute name="InitialContext"> javax.naming.IntialContext </attribute>
    <attribute name="RemoteAccess">false</attribute>
</mbean>

Your java code to perform the lookup then becomes:

 Context initialContext = new InitialContext();
 return initialContext.lookup("external/server2/" + jndiName);

You can even navigate the remote JNDI tree using JNDIView in the local management console when you set this up.

More information can be found in org.jboss.naming.ExternalContext MBean.

Well, I found another solution.

I created a new file called jndi-remote.properties on the configuration directory from Jboss:

{jboss_home}/server/default/conf/jndi-remote.properties

And I access the file in Jboss config directory (System.getProperty("jboss.server.config.url")) from Java:

String fileName = System.getProperty("jboss.server.config.url") + "/" + "jndi-remote.properties";

Properties properties = null;
try {
    URL url = new URL(fileName);
    if(new File(url.toURI()).exists()) { 
        properties = new Properties();
        properties.load(url.openStream());
        LOGGER.info("The file " + "jndi-remote.properties" + " was loaded from " + fileName);
    }
} catch (MalformedURLException e) {
    //throw
} catch (URISyntaxException e) {
    //throw
} catch (IOException e) {
    //throw
} 

And initialize my InitialContext:

if (properties != null) {
    ctx = new InitialContext(properties);
}

Works :).