Item.IsFromMe property always returns false

I have been using the Item.IsFromMe property to check if a given email was sent from a user to himself.

When using Exchange Server 2007 or 2010 this works good, but in Exchange Server 2013 the property always returns false.

Here is a simple repro:

(Obviously I cleared the Inbox before sending an email from the user to himself)

ServicePointManager.ServerCertificateValidationCallback = delegate { return true; };

var service = new ExchangeService(ExchangeVersion.Exchange2013);

service.Url = new Uri("https://172.21.29.11/ews/exchange.asmx");
service.Credentials = new WebCredentials("jorgecorreia", "Balloc*013", "demo");

var result = service.FindItems(WellKnownFolderName.Inbox, new ItemView(1));

result.Items[0].Load(new PropertySet(ItemSchema.IsFromMe));

Console.Write(result.Items[0].IsFromMe);