title: Call Skype numbers from Silverlight
body: <p>I have a Silverlight application in which I display some phone numbers. I want that numbers to be displayed as links and when the user clicks on the links to be redirected to skype. (The same as on html).</p>
  
  <p>This is the equivalent in html (just to understand what i need):</p>
  
  <pre><code>&lt;a href="callto:+11 11 111 11 11"&gt; +11 11 111 11 11&lt;/a&gt;
  </code></pre>
  
  <p>In silverlight I tried with: </p>
  
  <pre><code>&lt;HyperlinkButton Content="{Binding}" NavigateUri="{Binding StringFormat=callto:\{0\}}" /&gt;
  </code></pre>
  
  <p>but I get System.InvalidOperationException: Failed to navigate to callto:+11 11 111 11 11.</p>
  
  <p>Does somebody knows a solution for this?</p>