A system that services international multimedia message calls includes an MMSC that determines from the destination MSISDN of the header of a multimedia message that the call is an international transmission and, at the same time, determines whether or not the forwarding destination supports number portability, by referencing the MSISDN routing table. If number portability is supported, it acquires the IMSI corresponding to the destination MSISDN by inquiring the HLR. Next, the MMSC acquires the domain name of the MMSE of the forwarding destination by referencing the IMSI routing table from the IMSI that has thus been acquired and forwards the multimedia message to this MMSE. If number portability is not supported, it forwards the multimedia message to the MMSE of the domain name acquired by referencing the MSISDN routing table.