I have an iPhone 3G, and I'm supposed to be on that 20 cents per text message plan, but text messaging does not work for me. I tried using that "send a text message" feature on AT&T's web site to send a text to myself, and I never got it. I also had a friend send a text message to me, and I never got it. I also tried sending a text to my friend, and he never got it. Any idea what's wrong? Do I have to enable text messaging? I don't see that option when I log into my account on the AT&T web site.