Disallow index.html file

adverse effects?

[yowza]

My home page can currently be accessed as www.example.com/ or www.example.com/index.jsp.

I would like to block index.jsp in my robots.txt file. This won't have any adverse effects, will it? Being the home page, I was kind of worried about disallowing it.

The reason for blocking access is that index.jsp often has a query string attached to it, and I don't want any pages with query strings to be indexed. Alternate navigation is provided without query strings and I believe it is causing a dupe content penalty.