iPhone app InputAccessoryView isn't appearing on iPad

Question

I'm using Monotouch to develop an app for the iPhone.

In my iPhone only app, I have an InputAccessoryView appear whenever the user selects a textfield. The accessory view provides buttons which aid the user (undo/redo etc).

It works fantastically on the simulator and on iPhone devices.

However, out of the blue, the Input Accessory View is not appearing on the iPad. I've made no changes to the code regarding the views; I've even rolled back to a version that I know displayed the accessory view correctly.

I was wondering if anyone else has come across this behaviour before / would know why this is happening?

EDIT

I've seen this accross all of my iphone projects running on the ipad. I made a fresh project which only contains 1 view, a UITextField and override the Input Accessory View and I'm still seeing nothing.

Code I'm using to test the override of the input view is:

public override UIView InputAccessoryView
{
   get
   {
      UIView view = new UIView(new RectangleF(0,0,320,30));
      view.BackgroundColor = UIColor.Blue;
      return view;
   }
}

Nothing too complex, on the iPhone just returns a blue bar above the keyboard.

I've reinstalled Mono, MonoDevelop, Monotouch and the iOS SDK multiple times to no avail. Apps that I've downloaded from the store still show the Input Accessory View, so I'm beginning to wonder if it's an issue with my Monotouch/iOS SDK combo? I'm using Monotouch 3.1.3 personal and 4.1 iOS SDK - version 2.6 of Mono. I'm going to try updating to version 2.8 of Mono.

The thing I don't understand is why it would work previously then all of a sudden just stop working?

When I'm deploying the code on the iPad, I'm selecting "Rebuild all", then uploading to the device. It doesn't matter if I pick either Release/Debug as a build, both yield the same result.

EDIT 2

If I subclass a UITextField and override the InputAccessoryView within that subclass, then the view appears on the iPad. This means that the InputAccessoryView which is being overriden in the View class isn't being assigned to the Textfield on the ipad.