How to block a person's SMS and calls on my Iphone 4 without jailbreaking?

Well… I have this person who keeps calling and messaging me almost everyday.So, I would like to block this person on my I-phone. Yea… I know that the easiest way to change my number. But, it's not worth it to change my num just for one person. Could anyone help me how to do it? I don't want to jail break my iphone. Oh… Yes. I'm using iOS 6.

Ring up your phone network and ask them to block the number

Http://www.facebook.com/GeRates.Info