JBossMQ offers many transport mechanisms all of which can be configured to run in plain text mode or over ssl.
UIL2ConnectionFactory - this is the prefered connection factory (uses a single tcp/ip connection from client to server).
OILConnectionFactory - uses two tcp/ip connection factories, one from client to server, the other from server to client.
RMIConnectionFactory - uses two RMI connections, client->server and server->client
HTTPConnectionFactory - a servlet that allows transport over http - uses polling to deliver messages