ning.http.client Kerberos Example

Question

How can I support Kerberos based authentication with the ning http client?

I am extending existing code which has support for NTLMAuth and I want to be able to include support for Kerberos, which is used on some of the websites that I need to test.

I want to be able to put in the user and password programmatically, I do not want to use a keyTab, or setup krb5 configuration on the system where this is running.

I have the following code block;

import com.ning.http.client.RequestBuilder;
import com.ning.http.client.Realm.RealmBuilder;

....

        RealmBuilder myRealmBuilder = new RealmBuilder()
                .setScheme(AuthScheme.KERBEROS)
                .setUsePreemptiveAuth(true)
                .setNtlmDomain(getDomain())
                .setNtlmHost(getHost())
                .setPrincipal(getUsername())
                .setPassword(getUserPassword()));

        RequestBuilder rb = new RequestBuilder()
                .setMethod(site.getMethod())
                .setUrl(site.getUrl())
                .setFollowRedirects(site.isFollowRedirects())
                .setRealm(myRealmBuilder), 
                site)

´´´

Currently I get the error response: 
FAILED: Invalid name provided (Mechanism level: KrbException: Cannot locate default realm)

Does anyone have an good example of how to do this correctly?