You'll find a morse code program written by Richard Nelson in the Feb-Mar 1980 PPC Journal (V7 N2) on pages 50 and 51. I didn't take the time to do a exhaustive search but I'd guess that many more such programs exist for the 41CX.
This is not the complete text-to-morse solution, but tones 6 and 54 get you about 4wpm, 7 and 87 get you about 12wpm, and tones 73 and 57 get you about 40wpm. At the slower speeds you'll need to add some delay between tones.