NUnit 3.0 ExpectedResult is always null
<p>Migrating tests from NUnit 2.x to 3.x I replaced Result attribute with ExpectedResult for every TestCase. Anyway seems that ExpectedResult does not get the value passed.</p>

<p>My Code:</p>

<pre><code>[TestFixture]
public class HashToolsTest
{
        [TestCase("Cantami o diva del pelide Achille l'ira funesta", ExpectedResult = "b4dd7f0b0ca6c25dd46cc096e45158eb")]
         public object MD5_Should_Hash_a_string_according_to_MD5_standards(string toHash) {
              string res = HashTools.MD5(toHash);
              return res;
         }
 }
</code></pre>

<p>and when i run the tests message is:</p>

<pre><code>Expected: null
But was:  "b4dd7f0b0ca6c25dd46cc096e45158eb"

at NUnit.Framework.Assert.That(TActual actual, IResolveConstraint expression, String message, Object[] args) 
at  NUnit.Framework.Assert.AreEqual(Object expected, Object actual)
</code></pre>

<p>What did I miss?</p>