Unlocked iPhone not recognizing my SIM card

So heres my deal... My provider is TMobile and I had a 2G phone unlocked and jailbroken through QuickPwn. It always worked fine and I never had a problem with it. I came across a 3G phone and bought it. I reset everything on the phone and it locked itself. I then unlocked it and stuck my sim card in it. I also synced it with my Itunes so I could get my contacts and everything back. But for some reason its not recognizing my sim card. All it shows is one littler bar and then a bunch of smaller ones like a small line. It doesnt say my provider or have full bars at all. I cant make calls or do anything. When I put my sim card in an older phone it works perfectly. Anyone know what I have to do? I really do not want to have to get another sim card. I wouldnt even know what to tell TMobile cause they obviously know I dont have a 3G Iphone cause they dont sell them there. So what can I do? The phone is unlocked and I can do everything but call and text on it. Thanks!

I don't have an iPhone myself but I could safely guess that this has to do with unlocking your phone, something that you aren't supposed to do. Does the phone work if you put in the SIM card that you are supposed to use with the phone?

No u can unlock it... I have the newest version. I think its 2.2.1 maybe? I unlocked it with QuickPwn and I can listen to music on it and do everything so I did unlock it. Its just not reading my sim card. Its Model MB046LL

I agree that you can unlock it but you're not supposed to do so (difference between being able and being permitted). My earlier issue still stands in that it is probably the unlocking that's causing problems and that you should consider working backwards towards what the phone is supposed to be to see if that is indeed the cause. So, for example, replace the SIM to see if it's the SIM or the "pwn" of the phone. If that doesn't solve the problem, try restoring it back to factory settings to see if that fixes it.

You need to unlock the 3g iphone with your sim card in it. At least that is what I had to do when I unlocked an iphone a few months ago.

"not supposed to unlock it" - vansmith, you are only sort of right. *Apple* doesn't WANT you to unlock it, but it is legal to do so...so there is no "not supposed to" about it. It is, of course, less supported than staying on at&t.

T-mobile is happy to have iphone users, too. So don't worry about telling them. In fact, they have a special department set up to deal with network issues for non-tmobile phones like the iphone.