rest api authentication returning 404

Hi all,

I'm trying to use the Jenkins plugin against 12.2 but I'm getting an http 404 ("not found") right at login.  Since the plugin is open source, I used the remote debugger to see that it's trying this URL:

http://myserver:myport/LoadTest/rest/authentication-point/authenticate

Sure enough, that doesn't exist.  I read online that one can login via a browser like this, which works fine:

http://myserver:myport/qcbin/rest/is-authenticated?login-form-required=y

Is there something else that needs to be enabled on the server for the plugin to work or is the plugin wrong?

thanks

john