38. The computer program product according to claim 36 , wherein in the document call request accepting step, as the request of the method, a request for a content element of the desired node specified by the document ID is accepted, and wherein in the returning step, when the request for the content element of the desired node specified by the document ID has been accepted in the document call request accepting step, the content element of the desired node specified by the document ID is returned to the client apparatus making the document call request.
36. The computer program product according to claim 35 , wherein in the document call request accepting step, together with the document ID, a request of a method that designates information to be returned to the client apparatus is accepted, and wherein in the returning step, when the connection to the desired node specified by the document ID has been made in the connections making step, the information designated by the method is returned to the client apparatus making the document call request.