My iMessages on Iphone 4s is not working

Ok so I went on setting and put imessages on. I'm texting my boyfriend (who has an Iphone 4) and the text bubbles are not blue they are still green. Does the fact that my iphone is upgraded to ios 5.1.1 is the problem? Or is it something else?

Imessage only works under Wi-Fi.both partys need to be on Wi-Fi.

  • Why will my iPhone not receive iMessages for my phone number? I bought an unlocked iPhone and i was texting people through iMessage when I had Wi-Fi. Now I'm getting messages through normal texts only. When I go to the "Send & Receive" option under message settings, my phone number is there but it is gray in color and I can't select it. All the email addresses on the account can be selected but not my phone number. Can anyone help me?
  • Why isn't iMessages working on my iPhone? So earlier today I was able to use iMessages on my phone perfectly fine. But I just got an iMessage from my friend ( who I had been texting on my iPhone) on my iPod. And when I looked at my phone to see if it had shown up on there as well, it didn't. The message only sent to my iPod. But I can still receive normal texts on my phone from non-iPhone users. Anyone know what I should do?
  • Why is my Iphone not sending as Imessages and receiving iMessages from one person? I'm texting my wife and we both have iPhone's and she is getting the messages as an iMessage but the ones I'm sending her on my end show up at green. Sometime it will go as blue, get the little red exclamation point then send as regular SMS. I'm texting someone else too and she has an iPhone, and she is getting mine as regular iMessages and mine are sending as regular iMessages. Why aren't they sending to me wife as iMessages?
  • Why is my iPhone 4 not receiving iMessages So for about a week now my phone will send iMessages but it won't receive them. So I have tried turning iMessages off then back on I have tried turning my phone off and on and I don't know what to do know. Please help! I can add details if needed and any answer is much appreciated.