Solution : https://service.sap.com/sap/support/notes/1484695 (SAP Service marketplace login required)
Key words :
st-pi 2008_1 related, st-pi support package 3, sap service sessions, ewa service session, tab 'xml data, function /sdf/ewa_get_parameter, function /sdf/ewa_check_osmon, sap kernel default, original xml file, attached coding correction