title: CalendarWeeks in WPF Datepicker
body: <p>As the title of my question says: Is there a possibility to show the correspodending CalendarWeek in the WPF DatePicker-Control?</p>
  
  <p>With WinForms there was the possibility to show it on the left-hand-side of the calendar. How to achieve this in WPF?</p>
  
  <p><strong>UPDATE:</strong> Thanks to the good answer of <code>Mare Infinitus</code> I were able to find the correct (working for me) solution in the blog of <a href="http://www.charlespetzold.com/blog/2009/10/Adapting-the-Calendar-Control-for-Week-Numbers.html" rel="nofollow">Charles Petzold</a>.</p>
  
  <p>I just had to change the logic to calculate the weeknumber to pass iso-standards! :)</p>