Blackberry typing?

I just got a new PDA. This one has an itty-bitty QWERTY keyboard at the bottom, Blackberry-style, instead of handwriting recognition.

I've been touch-typing on a real keyboard for years, and suddenly I'm reduced to hunting and pecking with my thumbs.

Is there such as thing as a typing tutor for thumb keypads? "Mavis Beacon Teaches Crackberry," perhaps?