How do you activate the phone part of your iphone?

I just got one yesterday, and set it up with itunes, have everything in it, but i still cant use the phone aspect of it, it shows i have no bars or whatever, and i cant call or recieve calls or text or set up voicemail or anything. Is this simply a matter of waiting for it to activate and for my old phone to deactivate, or do I have to do something?

You will need to call at&t so they can "push" your activation thru. sometimes it will get stuck in the auto activation. Call at&t, you may need to give them the EMSI number on the sim card. To remove sim card, you will need a pin, paper clip works fine...

insert pin into small hole on top of phone...sim card holder and sim card will pop out. You will need to give them the last 5/6 digits of the sim card.

You should be good to go!!!!