Rosy Writer sample code not working or implemented wrongly

Hi,

I tried to implement the sample code for "RosyWriter" from

http://docs.xamarin.com/samples/RosyWriter/

but I think either something is wrong with the code. I am getting the following errors.

'MonoTouch.AVFoundation.AVCaptureAudioDataOutput' does not contain a definition for 'SetSampleBufferDelegateQueue' and no extension method 'SetSampleBufferDelegateQueue' accepting a first argument of type 'MonoTouch.AVFoundation.AVCaptureAudioDataOutput' could be found (are you missing a using directive or an assembly reference?)

'MonoTouch.AVFoundation.AVCaptureVideoDataOutput' does not contain a definition for 'SetSampleBufferDelegateQueue' and no extension method 'SetSampleBufferDelegateQueue' accepting a first argument of type 'MonoTouch.AVFoundation.AVCaptureVideoDataOutput' could be found (are you missing a using directive or an assembly reference?)