title: Binding Obj-C Categories in MonoTouch
body: <p>I am trying to bind WEPopover over to MonoTouch using btouch. It uses a <code>UIBarButtonItem</code> category implementation to extend it's functionality to include presentation of the popover.</p>
  
  <pre><code>@interface UIBarButtonItem(WEPopover)
  
  - (CGRect)frameInView:(UIView *)v;
  - (UIView *)superview;
  
  @end
  </code></pre>
  
  <p>How would I go about binding this into MonoTouch using a btouch interface definition?</p>