backbonejs + cors and save() method - backbone.js

Question

I'm trying to execute a POST throw the save method. Here is my model.
app.Models.Dummy = Backbone.Model.extend({
initialize: function () {
url = 'http://anotherdomain/Hello/';
},
});
When i execute:
dummy.save({text : "greg"}, {
success : function(){
console.log('Ok!');
},
error: function(){
console.log('Error');
}
});
The request is fired with an OPTIONS header (code 200) but the POST request is never fired.
However When i execute:
$.ajax({
type: 'POST',
url: "http://anotherdomain/Hello/",
data: {text:"greg"},
success: function(r) { alert(r.Result) },
dataType: "application/json"
});
it's works!
Does i need to override something in backbone?
EDIT:
The request is:
OPTIONS http://anotherdomain/Hello/ HTTP/1.1
Host: anotherdomain
User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:17.0) Gecko/17.0 Firefox/17.0
Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8
Accept-Language: fr,fr-fr;q=0.8,en-us;q=0.5,en;q=0.3
Accept-Encoding: gzip, deflate
Connection: keep-alive
Origin: http://mydomain
Access-Control-Request-Method: POST
Access-Control-Request-Headers: content-type
Pragma: no-cache
Cache-Control: no-cache
and the response is:
HTTP/1.1 200 OK
Cache-Control: private
Content-Length: 0
Server: Microsoft-IIS/7.5
Set-Cookie: ARRAffinity=611c389e4fd6c5d83202b700ce5627f6e0850faf0604f13c25903b4662919f36;Path=/;Domain=anotherdomain
X-AspNet-Version: 4.0.30319
X-Powered-By: ASP.NET
X-Powered-By: ARR/2.5
X-Powered-By: ASP.NET
Date: Wed, 05 Dec 2012 18:44:27 GMT

Answer 1

That's not a valid OPTIONS response for CORS. The response needs to include headers that tell the browser what's allowed. For example (taken from MDN):
Access-Control-Allow-Origin: http://foo.example
Access-Control-Allow-Methods: POST, GET, OPTIONS
Access-Control-Allow-Headers: X-PINGOTHER
I know you said that the $.ajax worked but based on this CORS response I doubt that is accurate and suggest you double check. Under the covers, backbone is itself just using $.ajax