Solution : https://service.sap.com/sap/support/notes/1501345 (SAP Service marketplace login required)
Key words :
category xiserverarea internal code attribute_initial, sap netweaver exchange infrastructure, additional central pi system, http multipart document, relevant support package, unique content id, attribute manifest <attachment-, additional attachment, message package, relevant payloads
Related Notes :
| 1583745 | XI Runtime: MMF message split DUPLICATE_CONTENT_IDS |
| 1511517 | SAP EHP1 FOR SAP NETWEAVER PI 7.1 SP06 |
| 1511515 | SAP Netweaver for PI 7.10 Support Package 11 |