When I first got my Captivate and turned on WIFI the WIFI symbol would pop up and take the place of the 3G symbol at the top but lately I've noticed that when I turn on the WIFI both symbols remain at the top. I have the unlimited data plan so using up data is not a problem for me. I'm just worried about battery life. Is my phone using both at the same time? Is that even possible? How do I go about fixing this?