Um, I don't mean to be cheeky, really, but correct me if I'm wrong -- it sounds like perhaps you would have saved yourself 75% of your bosses time and money if you had just done it in Java to begin with?
Altho, from your description of the app, it would have taken you about 3-4 days in Java. That's one servlet. Or am I mistaken?
I honestly don't mean to be dense, if I'm missing something. It's just an odd thing you said.
Except that we are an all-Microsoft shop with no Java expertise on staff (except me, and mine is dated). Java would have been a better solution for the original ASP application, but I can't see it being an improvement over the ASP.NET version.