Used old SIM, because new one didn't work. OK?

[cryo]

Since the activation problems began when I was purchasing the phone today, they sent me home to activate, but apparently the new SIM in the 3G never got activated, because when I finally got onto iTunes and registered the phone, the phone was showing no service, and it was clear the SIM never got activated. Once I registered the 3G, though, I decided to try my old 3G SIM card, and it worked perfectly for voice and data, so the phone doesn't appear to require the new SIM at all, which I've never had to use in an upgraded phone anyway.

So, the question is, will this be a problem down the road at all? I signed the contract in the store, so my account now shows my new upgrade date, and my account shows I have the $30 data plan for the 3G, so does it really matter I don't have the new SIM activated in the phone? I am trying to save a trip back to the store and further headache.

Thanks for any replies!

 

[scaredpoet]

You should be absolutely fine. The SIM that came with your old iPhone was 3G capable to begin with (as were all AT&T SIM cards distributed with all new AT&T phones that time, and going forward).

The store reps will try to activate with the new SIM simply because that's what's already in the phone. But t doesn't HAVE to happen that way.

To be sure, I can confirm that my old and new SIMs look exactly the same.