Get Appointment Body from a Room Resource Calendar

Question

According to this article, using a combination of FindItem and GetItem it should be possible to retrieve the notes section from an appointment.

This seems to work fine for a USER mailbox but fails when executed against a room resource mailbox. Is there a way to retrieve the message body from from an appointment in a room resource mailbox? Body.Value just returns null on a resource mailbox but the same code works fine on a user mailbox.