Network issue. Weird problem resolving host

Hi,
I have an issue with some forms that I’m sending to the server. It’s a weird problem because this script were made months ago and work fine. I checked the server and it’s working fine too, in fact, it works fine the first time I run unity but after this is not able to connect again. It’s working every time I reboot unity or the computer but I get this error later:
“Resolving host timed out: myhost.myhost”
I’m using Unity4.6.3 pro and my code is:

 public void Login(string nickname, string password)
    {
        string url = urlBase + "login.php";

        WWWForm form = new WWWForm();
        form.AddField("username",nickname);
        form.AddField("password", password);
        WWW www = new WWW(url, form);

        StartCoroutine(WaitForRequest(www, QueryType.Login));
    }

Edit: I’ve Uploaded the project to Unity 4.6.41f

Of course it’s a problem that I’m having with unity, a bug. Is there a patch that maybe could resolve this issue?