Error when defining the collection

[PolGuixe]

I am getting this server error:

 RangeError: Maximum call stack size exceeded

When:

  userstamp: {
      hasCreatedField: true,
      createdFieldName: 'createdBy',
      createdFieldOptional: false, // must be true to allow inserts by anonymous users
      hasUpdatedField: true,
      updatedFieldName: 'updatedBy',
      updatedFieldOptional: false, // must be true to allow updates by anonymous users
      usersCollection: Meteor.users
    }

But with:

  userstamp: {
      hasCreatedField: true,
      createdFieldName: 'createdBy',
      createdFieldOptional: false, // must be true to allow inserts by anonymous users
      hasUpdatedField: true,
      updatedFieldName: 'updatedBy',
      updatedFieldOptional: false, // must be true to allow updates by anonymous users
      //usersCollection: Meteor.users
    }

So I guess that it is related with the collection definition