That reminds me of the approach taken by many contact forms for members of the US congress. I believe the vendors have to follow certain security processes which includes sending the user to a 404 page if certain malicious attempts are detected. The end result in many cases is that there is a list of words that can not be submitted successfully through their form that changes over time and just check in certain fields based apparently on however the vendor wants to implement the security measure. Is your name Walter? Sorry but you sound like a sql injection attack so we will redirect you and the message you just spent an hour on over to a 404 page.