jabberd -- domain spoofing in server dialback protocol

XMPP Standards Foundation reports:

Some implementations of the XMPP Server Dialback protocol
(RFC 3920/XEP-0220) have not been checking dialback
responses to ensure that validated results are correlated
with requests.
An attacking server could spoof one or more domains in
communicating with a vulnerable server implementation,
thereby avoiding the protections built into the Server
Dialback protocol.