Ember 2.2.0: this.lookup is not a function

I updated from Ember 2.0.0 to 2.2.0 and no I get this "this.lookup is not a function" error when trying to get my custom authenicator.

In my controller I'm doing this:

  var authenticator = self.lookup('authenticator:custom');
  authenticator.signup(data)
  .then(function(data2) {

I simple can't find the new proper way to lookup the service.

Thx for help