If you stumble upon the following error:
See nested exception; nested exception is: javax.management.JMRuntimeException: ADMN0022E: Access is denied for the getChain operation on TransportChannelService MBean because of insufficient or empty credentials.
that means you need to revise your application permissions settings. That is, your application most probably has a RunAs role defined, which determines identity that is being mapped to each appliacation call - WebSphere then "thinks" that each call to this EJB is being made by some specified user (RunAs).
To check this, go to:
Applications > Enterprise Applications > application_name
and find Map RunAs roles to users under Additional Properties section. There you will find RunAs roles defined for this particular EJB. What you need to do is to type in valid username and password (having necessary permission level if you are using any authorization system - either role-based or external, like calling PDContext for TAM authorization), tick roles you want to assign them to and use Aplly, then save, synchronize and restart server.
Detailed information can be found on IBM InfoCenter.
Good luck, leave a comment or vote in the poll, please :)