Andrew,
If your question is whether you can set a key that you can press (and keep pressed) for a second or two and have it call an assigned number, then the answer is that this is a built in feature beginning in Handheld software 3.7.1.41.
If you want to have an icon on the main screen ribbon that will dial a number when selected - this is far more complex. As far as I know, the API for sing the phone in buried deep in the bowels of the OS - rumor is that it will be readily available in OS4.0. Like everything else
Ian
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