title: Caliburn.Micro with label not binding by convention
body: <p>I have been using Caliburn.Micro's binding via convention in Silverlight 5 and am loving it.  Here is an example property from a ViewModel:</p>
  
  <pre><code>private String _vmStringProp = "";
  public String VmStringProp
  {
      get
      {
          return _vmStringProp;
      }
  
      set
      {
          _vmStringProp = value;
          NotifyOfPropertyChange(() =&gt; VmStringProp);
      }
  }
  </code></pre>
  
  <p>This property is bound in the View just by naming: </p>
  
  <pre><code>&lt;TextBox x:Name="VmStringProp" /&gt;
  </code></pre>
  
  <p>This works great.  But if I change it to a TextBlock or Lable (example below) an exception is thrown.</p>
  
  <pre><code>&lt;sdk:Label x:Name="VmStringProp" /&gt;
  </code></pre>
  
  <p>It works fine if you change it to bind like normal Silverlight but I would rather keep consistent throughout the project instead of having some bound via convention and others explicitly bound depending on what type of control.  Does anyone know why I can't bind via convention with Labels and TextBlocks?</p>