Mobile video telephone method

A method of providing mobile video telephony service in a 3G mobile phone network to an inbound roaming mobile phone user from a 2G mobile phone network, comprises steps: (a) providing a system server connected to the 3G and 2G networks; (b) obtaining by the server the location of the user in the 3G network; (c) obtaining by the server from a home location register of the 2G network a subscriber profile with a features list including a 2G mobile phone number of the user; (d) revising by the server the features list of the subscriber profile by activating video telephony service and replacing the 2G mobile phone number with a 3G local mobile phone number; and (e) updating by the server the revised subscriber profile of the user at a mobile switching center of the 3G network, thereby enabling the user to make an outgoing video call in the 3G network.