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Did you cut it or did they cut it for you?

Neither. It is factory-built that way, specifically targeting unlocked iPhones users who want to use the phone on their network.

Before that, I had cut my original SIM card.

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When you activate it with an AT&T sim, take sim out, and plug the phone into itunes, does it say it is unlocked?

Nope. Just tells me the basic info:
Name
Serial Number
Capacity
etc..
 
Neither. It is factory-built that way, specifically targeting unlocked iPhones users who want to use the phone on their network.

Before that, I had cut my original SIM card.

Strange. Didn't know TMO made micro sims. Before panicking though, I would take it in to Apple, with your sim. Show them what is happening. The serial says it should be unlocked, so they should be able to replace it for you.
 
Strange. Didn't know TMO made micro sims. Before panicking though, I would take it in to Apple, with your sim. Show them what is happening. The serial says it should be unlocked, so they should be able to replace it for you.

Did that yesterday. They said it didn't show up as unlocked in their system. Yet they couldn't explain the signal issue...

They wouldn't let me trade it in.

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UPDATE:
Well, I just sold it on Craigslist for $500. Better than nothing I suppose.
Lesson=learned, lol.

Tomorrow's adventure: buying a factory unlocked iPhone 4S DIRECTLY from Apple :)
 
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