[Cryptography] Is Apple correct?

[Jerry Leichter]

>> If the firmware is programmed to only work on a phone with that specific IMEI number signed by Apple, am I correct that the firmware could not be modified to work on any other device since the signature would not match? 
> 
> Does anyone know whether the IMEI number stored inside tamper-resistant hardware in the phone? How difficult would it be to boot the same custom firmware in another phone, but arrange for the firmware to see the white-listed IMEI number?
This is the first mention I've seen of the IMEI.  I don't believe the IMEI is in any way involved in the iPhone security as being discussed here.  In fact, it pretty certainly isn't:  The same mechanism is present in iPads (and probably recent iPods) which don't (necessarily, in the case of iPads) have cellular hardware and hence IMEI's.
                                                        -- Jerry