Scrapping asp.net pages(aspx)

Hi Jeff

I read your book HTTP Programming Recipes for C# Bots and the book is really good. I have tried scrapping for some aspx pages. I just want to ask, does we need to create additional viewstate, eventvalidation etc for aspx pages because I have tried your code which you mentioned in chapter 8 Cookies for State 8.2. It works fine with link you have provided, and also I have tried scrapping for facebook which also works but when I used your code for aspx pages, it not works. There are two request in the url which I have tried. First request it works fine but in second it does not post the page and cookie collection count remains the same. Please provide solution for this.

Regards and Thanks,
Rajat Bhalla