Jailbroken iPhone "SIM Card Not Supported"

[Jarvian]

Hello everyone,

I have a jailbroken and unlocked iPhone 4 running (I believe but can't check to make sure) iOS 4.0.1 and setup on T-Mobile. It's worked fine since I purchased it at launch a year ago.

Today, while trying to use Mi-Time to setup Facetime on my phone, I used SAM to change the activation to Wildcard Activation. I hadn't yet begun the rest of the setup of my phone and gave it to a friend to make a call. They accidentally hit "Undo Activation" in SAM, and when I hit "Restore Activation" and plugged my phone into iTunes, I was told:

"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 visit a supported Carrier's store to receive a replacement SIM card."

I can't access the iPhone itself, except for the emergency call screen. Is there some way to get around that screen or re-jailbreak my phone without updating my baseband or losing my unlock?

Thanks to anyone who can help.

[Stray]

Use redsn0w 0.9.6 RC 8 I believe. Youll need to search Google for it.

[Jarvian]

Is there a way to confirm my firmware version? It's either 4.0.1 or 4.0.2. I don't think I ever updated to 4.1, but I need to select the correct IPSW for redsn0w.

[Stray]

Try using tinyumbrella. Search that in Google and its the first link

[xtacy]

F0recast will identify ur firmware :-)

[Jarvian]

Using redsn0w got me past the emergency screen and everything works fine now. Thanks for your help Str4y and xtacy.