title: Multilevel cocoa bindings
body: <p>When I bind to a multiple level keypath, say <code>objectValue.person.photo</code>, it does not update when the person changes, only when the photo changes. This would seem to be a problem with only the last key in the path being observed for changes.</p>
  
  <p>Is it possible to observe multiple levels of bindings? For instance, in SproutCore, if you place an asterisk in the path, everything after it will be observed for changes (<code>objectValue*person.photo</code>).</p>