ABAP.INTERFACE_REGISTRATION_ERROR while run SOAP - PI - RFC - R3 scenario.

Question

Hi all,
My scenario is a third party send a request (through SOAP message) to PI, then PI will made RFC call to R3 system to retrieve data.  (call BAPI_CUSTOMER_DISPLAY).
At IR i've created.
Namespace: http://send
1.  Data type: DT_request (which include customer number )
     Data type: DT_response
2.  Message type for 2 data types above.
3.  Message Mapping for request: MT_request  => BAPI_CUSTOMER_DISPLAY and for response: BAPI_CUSTOMER_DISPLAY.response => MT_response.
4. Service Interface: SI_BAPI_CUSTOMER_DISPLAY_REQUEST: Outbound, stateless and synchronous.
    Operator Mapping: which mapping SI_BAPI_CUSTOMER_DISPLAY_REQUEST and SI_CUSTOMER_DISPLAY_RESPONSE (please see 6).
At business system B (on R3 WS ABAP).
Namespace: http://rec
5. Importing BAPI_CUSTOMER_DISPLAY rfc.
6. Inbound Service Interface: SI_BAPI_CUSTOMER_DISPAY_RESPONSE: Inbout, statelss and synchronous (corresponding to  4.)
And then, at ID I've created:
7. SOAP communication channel (cc) for business system A. This cc is sender.
8. RFC communication channel for business system B. This cc is receiver.
9. Sender agreement, receiver determination...
10. Generate WSDL and got the ws url is: http://sapsrv:50100/sap/xi/engine?type=entry&version=3.0&Sender.Service=BVI&Interface=http%3A%2F%2Fsend%5ESI_BAPI_CUSTOMER_DISPLAY_REQUEST
Then,  I tried to test with XML spy but get this error:
<s:SystemError xmlns:s="http://sap.com/xi/WebService/xi2.0">
                         <context/>
                         <code>ABAP.INTERFACE_REGISTRATION_ERROR</code>
                         <text>No implementing class registered for the interface (ABAP interface, request message SI_BAPI_CUSTOMER_DISPLAY_REQUEST, request message, namespace http://send)</text>
PS: - I've generated all proxy at r3 system. (via tcode Sproxy)
         - And Sxmb_adm I've set Business System is Application System.
Please help me to fix this error.
Many thanks.

Answer 1

>>ABAP.INTERFACE_REGISTRATION_ERROR
You did not complete proxy objects coding yet.