RPN for Ti-89 Titanium?

Hello! I’m thinking of getting a Ti-89 Titanium because it seems like its some of the best hardware out there… But I’m a huge fan of reverse Polish notation. Does anybody know of a program that can give the Ti-89 TITANIUM RPN capabilities?

I’ve read about Lars Frederickson’s Ti-89 program - does it also work on a Titanium?

*Frederiksen