I am not able to connect to an XMPP server (Prosody) when encryption has been enabled on the server, even as an optional (not required) feature. The Hudson Jabber client reports a number of exceptions in the log, the salient message (I think) being:
javax.net.ssl.SSLException: Unsupported record version Unknown-105.113
(full log is attached)
However, if I enable Legacy SSL on the server and check the box in the Hudson configuration, it connects fine. Also note that Pidgin and Empathy clients connect to the server using standard TLS (not Legacy SSL) without issue.
After trying various combinations, I am led to believe that it is the Hudson client that is at fault, or perhaps the SMACK XMPP library that it appears to use. Or perhaps it is an interaction between this particular client and server.
I have a work-around in enabling Legacy SSL, but, as I understand it, this is a deprecated feature and not part of the standard, and I would prefer not to have to enable it on the server for just this one client.