Angularjs Java Rest Service 415 Unsupported Media Type

Im working with java spring mvc and angular js.

I created a rest service:

@RestController 
public class UserApiController { 

@Autowired
private UserService userService;

@RequestMapping(value = "/users/createUser", method = RequestMethod.POST)
public @ResponseBody void addUser(@RequestBody UserRequestDTO newUser) {
    userService.addUser(newUser);
}

And my angular controller like this:

var newUser = { surname : "orozco", name: "daniel", password: "pepe", email:"dani@dani.com" };
$http.post(getCompletePath("users/createUser"), JSON.stringify(newUser))
    .success(function () {
         alert("ok");
    }).error(function () {    
    });

It return the following error: 415 (Unsupported Media Type).

If I send a string o no parameters, it works. So, the problem is in the parameters