I've filed an enhancement request for supporting SSL certificates from the client side for XMPP.
the XMPP(S)Container will use a constructor of XmppConnection (smack
class) that will fail to connect if the server requires a cert to
The fix looks like upgrading the smack jar ECF points to and passing
a CallbackHandler via IConnectContext (if appropriate) to
XmppConnection using another constructor. In other words, change
XMPPContainer to pass a handler to XmppConnection to retrieve the
keystore password and then update the smack jar so that keystore types
such as Java Key Store (JKS) are handled correctly.