Very nice!
I have just tried to decipher the very same message but I got bunch of nothing, leaving me wondering did I screwed up something during the encryption process.
I'm glad that you managed to decipher it correctly. Now I have to track down where I made a mistake during decripting...
EDIT:
Hm...I done everything the same like you did, but when I entered indicator (WMYI) my output was completely different. Well ,
repetitio est mater studiorum...
