I don't think this will be any help to you, but I did something like this in lisp once. Only, it worked interactively, the vocabulary was built up from input sentences, and generation rules were generated essentially by building tables describing word proximity in input sentences. I called it "sputter". It was originally based on a program called "henley" which appeared in ANSI Common Lisp by Paul Graham which is a really good book if you want to learn Lisp.

Come to think of it, it was nothing like what you describe. It was a whole lot of fun though.

-sauoq
"My two cents aren't worth a dime.";