Messaging interfaces that may be used in conjunction with interactive pagers include a housing that contains a message processing circuit, a user interface, and a communications circuit that is used to forward the text messages between the message processing circuit and an interactive pager. The locking device may include a retaining pin and a deformable clamp element. The openings are aligned between the first and second ends. The acquisition module acquires a 2-dimensional image data group about the shape of an object represented by the 3-dimensional image data.