title: C# class using subclass does not implement inherited abstract member error
body: <p>Here's the c# code I'm trying to compile 
  Fairly simple, <code>testDMO</code> that inherits from <code>testDMOBase</code>
  Then test that inherits from testBase</p>
  
  <pre><code>public abstract class testDMOBase { }
  public class testDMO : testDMOBase { }
  public abstract class testBase
  {
      abstract protected void LoadCRUD(testDMOBase dmo);
  }
  public class test : testBase
  {
      override protected void LoadCRUD(testDMO dmo) { }
  }
  </code></pre>
  
  <p>I'm getting the following errors:</p>
  
  <blockquote>
    <p>'test' does not implement inherited abstract member
    'testBase.LoadCRUD(testDMOBase)' 'test.LoadCRUD(testDMO)': no suitable
    method found to override</p>
  </blockquote>
  
  <p>Shouldn't the use of a subclass be ok on the override method?</p>