Tmobile will do the same thing, but only if you've had the phone (and/or have been a customer, depending on who you talk to) for 90 days. Otherwise, you can just find the code online for as low as $10, but then you cut yourself out of the normal trial period. Not sure about how it effects the warranty.
**Tmobile users**Btw, if you have a Tmo 3G-capable phone in Mexico and it's roaming w/ the regular Tmo SIM card inside, you WILL get insane charges as it's constantly pinging for the 3G network and data roaming. Even if you leave your 3G phone sitting in your room and don't make any calls, it still roams, so be aware Tmobile customers!
**There is an easy free fix you can download for this online, though. Or, just switch over to the TelCel SIM card when you get into Mexico and you won't have to worry about it.**