So the story begins... I purchased my refurbished 16 gb iPhone 3g off of AT&T's website for $199.99. I received the phone a few days later. Also included in the box was a new 3g SIM card. I did a little research on the internet to see if I could use my old 3g card from my sony ericsson, all answers turned up "yes". So, i went ahead and popped it in, avoiding activation through AT&T, as well as loss of all my contacts. Everything was going swell until I checked my account on AT&T.com. Now, keep in mind that right after I upgraded my phone via the internet, AT&T's website showed that I was using an iphone 3g. This made me assume that it was perfectly okay to use my old SIM card, being that AT&T knew I was using an iPhone 3g with the $30 data plan... or so I thought. Under my phone number it displayed an overage of 157mb. I immediately needed a change of pants. After changing my pants, I contacted AT&T and explained my problem to one of their illegal immigrants via live chat. The man said "on my end I see that you are still using a sony ericsson and no iPhone data plan" (this would have been correct as of a few weeks ago) Then it hit me, this huge overage was caused by my ignorance during activation. I then explained what I had done and was told that I would have to pay all of the overage charges. I didn't feel like talking to my amigo any more on live chat, so I closed out. So, assuming the data plan will show up on my very large bill, do you think AT&T will reimburse me for my mistake, being that I was in fact paying for unlimited data, I was just simply using the wrong SIM card?