Tarek, you have raised 2 questions/issues here:
1) How to use ClientLoginModule on the remote client side to propagate a client side JAAS login information to the server during connection authentication
2) Once a remote connection has been established with the server using a specific credential, how to switch the credential on that remote connection, for subsequent usages of that connection.
#2 is currently not possible and that's what Darran meant when he said work is in progress to try and support it.
However, if you are looking for an example on how to do #1 then I just added an example to the quickstart guides here https://github.com/jaikiran/quickstart/tree/client-login-module/ejb-remote. You can run that quickstart to see it working. But you can even read the javadoc on this class and the referenced classes to understand how it all works https://github.com/jaikiran/quickstart/blob/client-login-module/ejb-remote/client/src/main/java/org/jboss/as/quickstarts/ejb/remote/client/callbackhandler/CustomServerLoginHandshakeCallbackHandler.java#L40.
I won't be able to write up an article on this today but plan to do soon. But I guess, those javadoc should give you can idea of how it can be achieved. If you have further questions, feel free to ask.