If you mean can you call the ESB using HTTPS then the answer is yes. We are doing that. I guess you are using jboss 4 while we are using jboss 5.1 GA but I can't think that this is a problem.
We didn't need to make a lot of changes. We made a server certificate we didn't change jboss-web.deployer server.xml file but the corresponding file for Jboss 5.1 GA to enable the https transport and to give the transport the correct certificate.
We are using a web service. A simple way to test that everything is setup fine is to try entering the https wsdl URL in a web browser at the client machine and see if you are getting a response.