Solution : https://service.sap.com/sap/support/notes/524172 (SAP Service marketplace login required)
Key words :
message_type_x abap runtime error occurs, 'unknown item reference type &1', /sapapo/cull1 message class, /sapapo/cl_cux_conv_stref class, message /sapapo/cuib1 009, /sapapo/cl_cux_conv_stref=====cp, /sapapo/cl_cux_conv_stref=====cm001, gc_apo_object_ext_stref private attribute, 'structure type crm_stpo, message number 014
Related Notes :
| 543403 | APO integration postprocessing during plug-in installation |
| 536066 | Missing class node components |
| 515499 | Release restrictions for R/3 Plug-In 2002.1 |