Solution : https://service.sap.com/sap/support/notes/561793 (SAP Service marketplace login required)
Key words :
/saphelp_nw04/helpdata/de/1f /93163f9959a808e10000000a114084/content, /saphelp_nw04/helpdata/en/1f /93163f9959a808e10000000a114084/content, import support package sapkb62012, relevant abap source code, cookie-based session handling, sap web application server, method if_http_server~set_session_stateful, default inactive due, web dynpro applications, attribute if_http_client~propertytype_accept_cookie
Related Notes :
| 1301591 | HTTP 400 - Session not found (Stateful HTTP communication) |