Solution : https://service.sap.com/sap/support/notes/638861 (SAP Service marketplace login required)
Key words : 
temporary object numberprogram saplbotmfunction group botmfunction module object_number_read_tm, terms general object number, temporary object numbers, object number management, time-consuming task, correction instructions belonging, object numbers, individual luw, logical unit, status management
Related Notes : 
       
| 644821 | Creating several WBS elements:CJ401 among others,termination | 
| 642635 | Performance Problem with SAPLKOBS form OBJECT_NUMBER_OR |