This week's book giveaway is in the OO, Patterns, UML and Refactoring forum. We're giving away four copies of Refactoring for Software Design Smells: Managing Technical Debt and have Girish Suryanarayana, Ganesh Samarthyam & Tushar Sharma on-line! See this thread for details.
Does the JSP file get executed at all? If yes, does it return anything? Perhaps the content type needs to be set correctly in the JSP code. At the following link you can find a complete AJAX example, using a JSP file: http://koenaerts.ca/a-complete-ajax-example/ The example uses a POST rather than a GET to send the request, which I would recommend because the GET URL has limitations on how long it can be, something like 1024 characters or something like it, I can't remember exactly.