This tutorial explains how to make a QML user interface entirely navigable by keyboard.
If you don't know anything about QML, reading the introductory Qt/QML documentation might be helpful.
I'm using Fedora 13 Linux here, and have run the application on that and MeeGo 1.1.
You basically need a QML application with some input elements to start with.
You then add keyboard navigation using the following QML elements:
KeyNavigation, for defining paths between pairs of UI elements (e.g. to move between input elements)
Keys, for connecting key presses to actions (e.g. to submit data entered in input elements)