Solution : https://service.sap.com/sap/support/notes/664727 (SAP Service marketplace login required)
Key words : 
terms get_item_info get_item_type check_item_type get_hdr_guid reason, function module calls crm_orderadm_i_read_ow unnecessarily, spent gettingitem information, attached coding correction, symptom crm_event_publish_ow, header guid, prerequisites
Related Notes : 
       
| 696262 | CRM 4.0 SP Stack 1/2004 (SAPKU40004): Release & Info. Note | 
| 670964 | Performace improvement for sales orders |