In response to a first location request message from a client terminal, a gateway stores the message and requests the location information of a target mobile terminal from a location information system. If a second location request message is received from other client terminal requesting the location information of the same mobile terminal while the initial client terminal is waiting for the requested information, the second location request message is stored. Reply messages are sent simultaneously to these client terminals when the requested information is received. In a modified embodiment, if location request messages are received from multiple client terminals for the same target mobile terminal, they are stored in a memory, which is then searched at periodic intervals. If the message of at least one client terminal is detected, the gateway acquires location information of the target terminal from the system and transmits a reply message to client terminals.