Solution : https://service.sap.com/sap/support/notes/1583973 (SAP Service marketplace login required)
Key words :
software component fs-ri financial servi, release 660 sapk-66005inmsg - sapk-66005inmsg, ------------------------------------------------------------------------create message /msg/7fs_messages 077, message class /msg/7fs_messages, create message /msg/7fs_messages 078, unknown extension type '&1' - 'em ', manual post-processing adjusted, support packages sapk-66006inmsg, existing extension service extensions, sapk-67001inmsg correct