partial unlock

Hello,

I'm from Brazil and I have a strange problem.

In 2010, I bought an iPhone 4 from TIM Brasil, local carrier, unlocked.

In 2011, my home button stopped to work and since it was in waranty period yet, I talked to TIM Brasil and send my iPhone 4 to the official tech assistence here in Brasil. As the home button problem was confirmed, this tech assistence change my iPhone 4, sending me another one, new.

As my old one, I think it was unlocked too.

Recently, I was planning a travel to Europe and I started to search for some ways to have my iPhone working there, for a small cost. I found Maxroam SimCard.

I decided to buy a simcard of Maxroam and when it arrived here in Brazil, I followed the instructions provided by Maxrom but it fail.

My iPhone tells that it is a Invalid SIMCARD and my phone is No Service. Then I tried to plug my iPhone 4 on iTunes to activate it with Maxroam SIMCARD, and I got back a message:

"The SIM Card inserted in this iPhone does not appear to be supported.

Only compatible SIM cards from a supported Carrier may be used to activate iPhone. Please insert the SIM card that came with your iPhone or visite a supported Carrier's store to receive a replacement SIM card."

Well, with this message, I have two ways of research:

1- My iPhone 4 is locked to TIM Brasil:

- I tried another SIMCARD from other local carriers and it works fine, so, my iPhone is unlocked;

- I search on imei.info about my hardware and, after pay a dollar, I got a report telling that my iPhone is unlocked;

- I call my carrier (TIM Brasil). They say that they can't find my hardware into their database, since my iPhone was changed by Apple (by its offical tech assistence in Brazil- Allied), so they could not unlock my iPhone 4.

2- My Maxroam SIMCARD is broken:

- I insert my Maxroam SIMCARD on my iPad - bought from TIM Brasil, and after follow those provided instructions by Maxroam, it works fine, get a Internation Roam with another local carrier;

- I did that same test with a friend of mine's iPhone 4, that belongs to another local carrier. After follow the same instructions, it works as well as in my iPad.

Conclusions:

- My Maxroam SIMCard is working fine, both on my iPad 2 and in my friend's iPhone 4;

- My iPhone 4, for some reason I really can't figure out, is partially unlocked: for local carriers, other then my own carrier TIM Brasil, is unlocked and works fine. For Maxroam SIMCARD it is locked.

I explain all that case to my local carrier assistance, and with a lot's of patience by both parts, they tell me that they could not do anything, since my iPhone was replaced by a Apple official assistance and they don't have my IMEI recorded on their databases. They also tell me to call Apple Suport and try to solve my problem.

As I could'n find any channel to call that Apple support in Brazil, I'm trying the community to help me.

Anybody could help me? Is there any Apple suport following community work?

Best regards.