I'm looking to force a user to log-off from ejabberd. I've just manually reset his password, and I'd like to cause all of his sessions to log off and back on, to make sure that only ones which know the new password are logged on.
Is this doable through the admin console (or any other method, really)?
Did you try mod_admin_extra ? It adds extra commands on ejabberdctl command line. You might be interested by the killsession command.
See mod_admin_extra: http://www.ejabberd.im/mod_admin_extra
and list of commands: http://www.ejabberd.im/mod_ctlextra