Karma PhamtonJS TypeError: 'undefined' is not a function (evaluating 'React.renderComponent

I'm trying to set up React component testing using Webpack, Karma and PhantomJS.

I cannot seem to find why I get the following error when I run npm test:

PhantomJS 1.9.8 (Windows 8 0.0.0) Module Header should display text FAILED TypeError: 'undefined' is not a function (evaluating 'React.renderComponent(instance, div)')

I have the following test file

'use strict';




describe('Module', function(){

  var component;

  beforeEach( function(){
    var React = require('react-addons');
    var TestUtils = React.TestUtils;
    var Header = require('../Header');
    var component = TestUtils.renderIntoDocument(<Header title="Test Title" />);
  });


  it('Header should display text', function(){

    expect(component.getDOMNode().textContent).toMatch(/Test Title/);
  });


});

It seems that TestUtils.renderIntoDocument(); is the problem , does anyone know how I can fix this ?

Thanks for your time.