The way you phrased it makes it sound like the illegality is something beyond the fact that it calls emergency services. Is that the case, and if so, what makes it illegal?
I'm not an expert, but I know some of them faked IMEI/IMSI/some acronym numbers to pretend to be from the official carrier for the iPhone. IIRC, that is also illegal (as is the emergency services call in the newer ones).
