Solution : https://service.sap.com/sap/support/notes/126201 (SAP Service marketplace login required)
Key words : 
additional key words unit, generate error message mm101 ', error message, additional symptom, implement note 112062, production order, alternative units, product costing, transaction ck11, source code
Related Notes : 
       
| 188705 | Components with component scrap incorrect | 
| 147672 | Header quanty change: Scrap not taken into account | 
| 132143 | MM104 or MM103 after implementation of Note 112062 | 
| 112062 | CO01/02:Incor. phantm qties when changing headr qty |