9. An apparatus for searching address book information, the apparatus comprising: A database for storing a search preference corresponding to a requesting client; and A server configured to: receive a search request message for searching for address book information using preference information of a requesting client form the requesting client; in response to receiving the search request message, obtaining address information of a plurality of external directories and the preference information representing at least one external directory preferred by the requesting client from an external server; check address information of at least one external directory form among the address information of the plurality of external directories based on the preference information and the address information; forward an external search request message to the at least one external directory using the address information of the at least one external directory; receive an external search response message including an external search result searched by the at least one external directory from the at least one external directory; prioritize the external search result and arranging the prioritized external search result; and forward a final search result including at least part of the arranged external search result to the requesting client, wherein the preference information further comprises information regarding application or non-application of a search preference to the search request of the address book information, information regarding application or non-application of the search preference to at least one external search domain corresponding to the at least one external directory, and information regarding application or non-application of the search preference for a dynamic search according to a user's location, and wherein the information regarding application or non-application of the search preference to the at least one external search domain comprises the at least one external search domain and a preference weight value per domain.
9. An apparatus for searching address book information, the apparatus comprising: A database for storing a search preference corresponding to a requesting client; and A server configured to: receive a search request message for searching for address book information using preference information of a requesting client form the requesting client; in response to receiving the search request message, obtaining address information of a plurality of external directories and the preference information representing at least one external directory preferred by the requesting client from an external server; check address information of at least one external directory form among the address information of the plurality of external directories based on the preference information and the address information; forward an external search request message to the at least one external directory using the address information of the at least one external directory; receive an external search response message including an external search result searched by the at least one external directory from the at least one external directory; prioritize the external search result and arranging the prioritized external search result; and forward a final search result including at least part of the arranged external search result to the requesting client, wherein the preference information further comprises information regarding application or non-application of a search preference to the search request of the address book information, information regarding application or non-application of the search preference to at least one external search domain corresponding to the at least one external directory, and information regarding application or non-application of the search preference for a dynamic search according to a user's location, and wherein the information regarding application or non-application of the search preference to the at least one external search domain comprises the at least one external search domain and a preference weight value per domain. 14. The apparatus of claim 9 , wherein the preference information further comprises information regarding application or non-application of the search preference to the external search result, information regarding application or non-application of a prioritized preference to the external search result, and filter information for filtering the external search result.