How to Create a quiz application using Survey template in SharePoint 2007?

Using "Survey" list template, I recently created a quizzing application. In my application I have a list with Question s, choices and answers. Using some object model I was able to make use of the SharePoint survey list template to organize a quiz within our organization.
I inherit some of the functionality from the following link. Sridhar has gave a start up idea for my requirement.
http://blogs.msdn.com/sridhara/archive/2008/12/15/howto-create-a-quizzing-application-with-sharepoint-2007.aspx
Using his tool I am able to create a Demo Exam to attend the employee. I am imitating the permissions to the lists from Sridhar.
Well, in the code, the Read/Write Securities for the survey list are set to 2, which means "Users have Read access only to items that they create" and "Write only my items" respectively. However, once a user answers all questions and submits the quiz, he/she can ‘t attend the test again.
Here the results are declare immediately.
The results are storing in a separate list . In that I am maintaining Employee Name, Date of attempt, Score. For this I am using ItemAdded Event handler.
I am creating a feature for this.