AuthenticationContext.AcquireTokenAsync crash with a given password

Hi!

I have this "simple" code:

        public static async Task<string> RetrieveTokenAsync()
        {
            var authContext = new AuthenticationContext("https://login.windows.net/MYTENANT.com/", true, new FileCache());
            try
            {
                AuthenticationResult result = null;
                result = await authContext.AcquireTokenAsync(Resource, ClientId, new Uri(RedirectUri),
                        new PlatformParameters(PromptBehavior.Auto), UserIdentifier.AnyUser, "domain_hint=MYTENTANT.com");
                if (result == null)
                {
                    throw new InvalidOperationException("Failed to obtain the JWT token");
                }
                // store token for reuse
                Console.WriteLine("AccessToken=" + result.AccessToken);
                return result.AccessToken;
            }
            catch (Exception ex)
            {
                throw new InvalidOperationException("Could not retrieve token.", ex);
            }
        }

        static void Main(string[] args)
        {
            try
            {
                RetrieveTokenAsync().Wait();
            }
        }	

When calling await authContext.AcquireTokenAsync in a computer that is not connected to Office 365 and I use an account belonging to an office365 account and I enter the user and password it crashes.

This only happens with that user and password... if I use another user but the same password then there is the same crash. So it seems that the problem is related to the password I use... quite strange. It's a simple password of 8 characters.

I tried compiling it against different versions of the Identity package but it's the same.

Any clue?

Thanks