I have an iphone here that was unlocked. It was then upgraded to 1.1.2, now for some reason its not working. I was not the original person who unlocked it so i dont know what the method was.

What I did was put it back to 1.0.2 and unlocked it, but it has no reception and another thing i caught was the IMEI is not the same as the back of the phone.

Can somebody help. Thanks

Does the new IMEI start with 0049, or is it some other number? The 0049 number is a sign that something is wrong with a portion of the baseband.

I did have the experience once of buying an iPhone from Apple that had an IMEI that was different than the one on the box, but that was just a screw up by Apple.

Yes it does start with 0049, How can i fix that?

downgrade, revirginize, upgrade & unlock again.