It should work, at least I hope so ;-) (The old) Fitaly and FitalyStamp do work together. Back when I had had a monochrome device I used both together. I 'm waiting for Fitaly 3 myself for better nighttime tapping. (Fitaly 3 is also the only solution for Fitaly on a Treo 270 / 300.)
You may want to repost your question on the regular Fitaly Forum
which is much busier.