> Does 112 work on 3G? If so, and you were out of Three and Vodafone
> coverage, will other GSM networks carry a 112 call from a Three handset?
"3G" in the sense of UMTS is just another evolution of GSM. 112 will work
from this. If the Three handset supports any of the additional GSM bands
(all of them do) emergency calls will be attempted on a foreign PLMN in
close to the usual manner.